diff --git a/include/ui/Input.h b/include/ui/Input.h
index 86ce098..e92d7f5 100644
--- a/include/ui/Input.h
+++ b/include/ui/Input.h
@@ -52,6 +52,14 @@
 };
 
 /*
+ * SystemUiVisibility constants from View.
+ */
+enum {
+    ASYSTEM_UI_VISIBILITY_STATUS_BAR_VISIBLE = 0,
+    ASYSTEM_UI_VISIBILITY_STATUS_BAR_HIDDEN = 0x00000001,
+};
+
+/*
  * Maximum number of pointers supported per motion event.
  * Smallest number of pointers is 1.
  * (We want at least 10 but some touch controllers obstensibly configured for 10 pointers
@@ -468,6 +476,11 @@
     status_t writeToParcel(Parcel* parcel) const;
 #endif
 
+    static bool isTouchEvent(int32_t source, int32_t action);
+    inline bool isTouchEvent() const {
+        return isTouchEvent(mSource, mAction);
+    }
+
     // Low-level accessors.
     inline const int32_t* getPointerIds() const { return mPointerIds.array(); }
     inline const nsecs_t* getSampleEventTimes() const { return mSampleEventTimes.array(); }
diff --git a/include/ui/Keyboard.h b/include/ui/Keyboard.h
index 54bc968..609f319 100644
--- a/include/ui/Keyboard.h
+++ b/include/ui/Keyboard.h
@@ -127,6 +127,11 @@
  */
 extern int32_t updateMetaState(int32_t keyCode, bool down, int32_t oldMetaState);
 
+/**
+ * Returns true if a key is a meta key like ALT or CAPS_LOCK.
+ */
+extern bool isMetaKey(int32_t keyCode);
+
 } // namespace android
 
 #endif // _UI_KEYBOARD_H
diff --git a/include/utils/Looper.h b/include/utils/Looper.h
index eefff31..3c2905d 100644
--- a/include/utils/Looper.h
+++ b/include/utils/Looper.h
@@ -45,6 +45,51 @@
 namespace android {
 
 /**
+ * A message that can be posted to a Looper.
+ */
+struct Message {
+    Message() : what(0) { }
+    Message(int what) : what(what) { }
+
+    /* The message type. (interpretation is left up to the handler) */
+    int what;
+};
+
+
+/**
+ * Interface for a Looper message handler.
+ *
+ * The Looper holds a strong reference to the message handler whenever it has
+ * a message to deliver to it.  Make sure to call Looper::removeMessages
+ * to remove any pending messages destined for the handler so that the handler
+ * can be destroyed.
+ */
+class MessageHandler : public virtual RefBase {
+protected:
+    virtual ~MessageHandler() { }
+
+public:
+    /**
+     * Handles a message.
+     */
+    virtual void handleMessage(const Message& message) = 0;
+};
+
+
+/**
+ * A simple proxy that holds a weak reference to a message handler.
+ */
+class WeakMessageHandler : public MessageHandler {
+public:
+    WeakMessageHandler(const wp<MessageHandler>& handler);
+    virtual void handleMessage(const Message& message);
+
+private:
+    wp<MessageHandler> mHandler;
+};
+
+
+/**
  * A polling loop that supports monitoring file descriptor events, optionally
  * using callbacks.  The implementation uses epoll() internally.
  *
@@ -166,6 +211,52 @@
     int removeFd(int fd);
 
     /**
+     * Enqueues a message to be processed by the specified handler.
+     *
+     * The handler must not be null.
+     * This method can be called on any thread.
+     */
+    void sendMessage(const sp<MessageHandler>& handler, const Message& message);
+
+    /**
+     * Enqueues a message to be processed by the specified handler after all pending messages
+     * after the specified delay.
+     *
+     * The time delay is specified in uptime nanoseconds.
+     * The handler must not be null.
+     * This method can be called on any thread.
+     */
+    void sendMessageDelayed(nsecs_t uptimeDelay, const sp<MessageHandler>& handler,
+            const Message& message);
+
+    /**
+     * Enqueues a message to be processed by the specified handler after all pending messages
+     * at the specified time.
+     *
+     * The time is specified in uptime nanoseconds.
+     * The handler must not be null.
+     * This method can be called on any thread.
+     */
+    void sendMessageAtTime(nsecs_t uptime, const sp<MessageHandler>& handler,
+            const Message& message);
+
+    /**
+     * Removes all messages for the specified handler from the queue.
+     *
+     * The handler must not be null.
+     * This method can be called on any thread.
+     */
+    void removeMessages(const sp<MessageHandler>& handler);
+
+    /**
+     * Removes all messages of a particular type for the specified handler from the queue.
+     *
+     * The handler must not be null.
+     * This method can be called on any thread.
+     */
+    void removeMessages(const sp<MessageHandler>& handler, int what);
+
+    /**
      * Prepares a looper associated with the calling thread, and returns it.
      * If the thread already has a looper, it is returned.  Otherwise, a new
      * one is created, associated with the thread, and returned.
@@ -201,12 +292,27 @@
         Request request;
     };
 
+    struct MessageEnvelope {
+        MessageEnvelope() : uptime(0) { }
+
+        MessageEnvelope(nsecs_t uptime, const sp<MessageHandler> handler,
+                const Message& message) : uptime(uptime), handler(handler), message(message) {
+        }
+
+        nsecs_t uptime;
+        sp<MessageHandler> handler;
+        Message message;
+    };
+
     const bool mAllowNonCallbacks; // immutable
 
     int mWakeReadPipeFd;  // immutable
     int mWakeWritePipeFd; // immutable
     Mutex mLock;
 
+    Vector<MessageEnvelope> mMessageEnvelopes; // guarded by mLock
+    bool mSendingMessage; // guarded by mLock
+
 #ifdef LOOPER_USES_EPOLL
     int mEpollFd; // immutable
 
@@ -256,6 +362,7 @@
     // it runs on a single thread.
     Vector<Response> mResponses;
     size_t mResponseIndex;
+    nsecs_t mNextMessageUptime; // set to LLONG_MAX when none
 
     int pollInner(int timeoutMillis);
     void awoken();
diff --git a/libs/ui/Input.cpp b/libs/ui/Input.cpp
index a80320e..0ed0866 100644
--- a/libs/ui/Input.cpp
+++ b/libs/ui/Input.cpp
@@ -616,6 +616,23 @@
 }
 #endif
 
+bool MotionEvent::isTouchEvent(int32_t source, int32_t action) {
+    if (source & AINPUT_SOURCE_CLASS_POINTER) {
+        // Specifically excludes HOVER_MOVE and SCROLL.
+        switch (action & AMOTION_EVENT_ACTION_MASK) {
+        case AMOTION_EVENT_ACTION_DOWN:
+        case AMOTION_EVENT_ACTION_MOVE:
+        case AMOTION_EVENT_ACTION_UP:
+        case AMOTION_EVENT_ACTION_POINTER_DOWN:
+        case AMOTION_EVENT_ACTION_POINTER_UP:
+        case AMOTION_EVENT_ACTION_CANCEL:
+        case AMOTION_EVENT_ACTION_OUTSIDE:
+            return true;
+        }
+    }
+    return false;
+}
+
 
 // --- InputDeviceInfo ---
 
diff --git a/libs/ui/Keyboard.cpp b/libs/ui/Keyboard.cpp
index 8b6300a..600a951 100644
--- a/libs/ui/Keyboard.cpp
+++ b/libs/ui/Keyboard.cpp
@@ -322,5 +322,26 @@
     }
 }
 
+bool isMetaKey(int32_t keyCode) {
+    switch (keyCode) {
+    case AKEYCODE_ALT_LEFT:
+    case AKEYCODE_ALT_RIGHT:
+    case AKEYCODE_SHIFT_LEFT:
+    case AKEYCODE_SHIFT_RIGHT:
+    case AKEYCODE_SYM:
+    case AKEYCODE_FUNCTION:
+    case AKEYCODE_CTRL_LEFT:
+    case AKEYCODE_CTRL_RIGHT:
+    case AKEYCODE_META_LEFT:
+    case AKEYCODE_META_RIGHT:
+    case AKEYCODE_CAPS_LOCK:
+    case AKEYCODE_NUM_LOCK:
+    case AKEYCODE_SCROLL_LOCK:
+        return true;
+    default:
+        return false;
+    }
+}
+
 
 } // namespace android
diff --git a/libs/utils/Looper.cpp b/libs/utils/Looper.cpp
index a5363d6..18f858b 100644
--- a/libs/utils/Looper.cpp
+++ b/libs/utils/Looper.cpp
@@ -19,10 +19,27 @@
 
 #include <unistd.h>
 #include <fcntl.h>
+#include <limits.h>
 
 
 namespace android {
 
+// --- WeakMessageHandler ---
+
+WeakMessageHandler::WeakMessageHandler(const wp<MessageHandler>& handler) :
+        mHandler(handler) {
+}
+
+void WeakMessageHandler::handleMessage(const Message& message) {
+    sp<MessageHandler> handler = mHandler.promote();
+    if (handler != NULL) {
+        handler->handleMessage(message);
+    }
+}
+
+
+// --- Looper ---
+
 #ifdef LOOPER_USES_EPOLL
 // Hint for number of file descriptors to be associated with the epoll instance.
 static const int EPOLL_SIZE_HINT = 8;
@@ -35,8 +52,8 @@
 static pthread_key_t gTLSKey = 0;
 
 Looper::Looper(bool allowNonCallbacks) :
-        mAllowNonCallbacks(allowNonCallbacks),
-        mResponseIndex(0) {
+        mAllowNonCallbacks(allowNonCallbacks), mSendingMessage(false),
+        mResponseIndex(0), mNextMessageUptime(LLONG_MAX) {
     int wakeFds[2];
     int result = pipe(wakeFds);
     LOG_ALWAYS_FATAL_IF(result != 0, "Could not create wake pipe.  errno=%d", errno);
@@ -161,17 +178,21 @@
     for (;;) {
         while (mResponseIndex < mResponses.size()) {
             const Response& response = mResponses.itemAt(mResponseIndex++);
-            if (! response.request.callback) {
+            ALooper_callbackFunc callback = response.request.callback;
+            if (!callback) {
+                int ident = response.request.ident;
+                int fd = response.request.fd;
+                int events = response.events;
+                void* data = response.request.data;
 #if DEBUG_POLL_AND_WAKE
                 LOGD("%p ~ pollOnce - returning signalled identifier %d: "
-                        "fd=%d, events=0x%x, data=%p", this,
-                        response.request.ident, response.request.fd,
-                        response.events, response.request.data);
+                        "fd=%d, events=0x%x, data=%p",
+                        this, ident, fd, events, data);
 #endif
-                if (outFd != NULL) *outFd = response.request.fd;
-                if (outEvents != NULL) *outEvents = response.events;
-                if (outData != NULL) *outData = response.request.data;
-                return response.request.ident;
+                if (outFd != NULL) *outFd = fd;
+                if (outEvents != NULL) *outEvents = events;
+                if (outData != NULL) *outData = data;
+                return ident;
             }
         }
 
@@ -194,6 +215,25 @@
     LOGD("%p ~ pollOnce - waiting: timeoutMillis=%d", this, timeoutMillis);
 #endif
 
+    // Adjust the timeout based on when the next message is due.
+    if (timeoutMillis != 0 && mNextMessageUptime != LLONG_MAX) {
+        nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+        if (mNextMessageUptime <= now) {
+            timeoutMillis = 0;
+        } else {
+            uint64_t delay = (mNextMessageUptime - now + 999999LL) / 1000000LL;
+            if (delay < INT_MAX
+                    && (timeoutMillis < 0 || int(delay) < timeoutMillis)) {
+                timeoutMillis = int(delay);
+            }
+        }
+#if DEBUG_POLL_AND_WAKE
+        LOGD("%p ~ pollOnce - next message in %lldns, adjusted timeout: timeoutMillis=%d",
+                this, mNextMessageUptime - now, timeoutMillis);
+#endif
+    }
+
+    // Poll.
     int result = ALOOPER_POLL_WAKE;
     mResponses.clear();
     mResponseIndex = 0;
@@ -205,7 +245,6 @@
 #ifdef LOOPER_USES_EPOLL
     struct epoll_event eventItems[EPOLL_MAX_EVENTS];
     int eventCount = epoll_wait(mEpollFd, eventItems, EPOLL_MAX_EVENTS, timeoutMillis);
-    bool acquiredLock = false;
 #else
     // Wait for wakeAndLock() waiters to run then set mPolling to true.
     mLock.lock();
@@ -219,16 +258,20 @@
     int eventCount = poll(mRequestedFds.editArray(), requestedCount, timeoutMillis);
 #endif
 
+    // Acquire lock.
+    mLock.lock();
+
+    // Check for poll error.
     if (eventCount < 0) {
         if (errno == EINTR) {
             goto Done;
         }
-
         LOGW("Poll failed with an unexpected error, errno=%d", errno);
         result = ALOOPER_POLL_ERROR;
         goto Done;
     }
 
+    // Check for poll timeout.
     if (eventCount == 0) {
 #if DEBUG_POLL_AND_WAKE
         LOGD("%p ~ pollOnce - timeout", this);
@@ -237,6 +280,7 @@
         goto Done;
     }
 
+    // Handle all events.
 #if DEBUG_POLL_AND_WAKE
     LOGD("%p ~ pollOnce - handling events from %d fds", this, eventCount);
 #endif
@@ -252,11 +296,6 @@
                 LOGW("Ignoring unexpected epoll events 0x%x on wake read pipe.", epollEvents);
             }
         } else {
-            if (! acquiredLock) {
-                mLock.lock();
-                acquiredLock = true;
-            }
-
             ssize_t requestIndex = mRequests.indexOfKey(fd);
             if (requestIndex >= 0) {
                 int events = 0;
@@ -271,9 +310,6 @@
             }
         }
     }
-    if (acquiredLock) {
-        mLock.unlock();
-    }
 Done: ;
 #else
     for (size_t i = 0; i < requestedCount; i++) {
@@ -301,15 +337,12 @@
             }
         }
     }
-
 Done:
     // Set mPolling to false and wake up the wakeAndLock() waiters.
-    mLock.lock();
     mPolling = false;
     if (mWaiters != 0) {
         mAwake.broadcast();
     }
-    mLock.unlock();
 #endif
 
 #ifdef LOOPER_STATISTICS
@@ -335,19 +368,59 @@
     }
 #endif
 
+    // Invoke pending message callbacks.
+    mNextMessageUptime = LLONG_MAX;
+    while (mMessageEnvelopes.size() != 0) {
+        nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+        const MessageEnvelope& messageEnvelope = mMessageEnvelopes.itemAt(0);
+        if (messageEnvelope.uptime <= now) {
+            // Remove the envelope from the list.
+            // We keep a strong reference to the handler until the call to handleMessage
+            // finishes.  Then we drop it so that the handler can be deleted *before*
+            // we reacquire our lock.
+            { // obtain handler
+                sp<MessageHandler> handler = messageEnvelope.handler;
+                Message message = messageEnvelope.message;
+                mMessageEnvelopes.removeAt(0);
+                mSendingMessage = true;
+                mLock.unlock();
+
+#if DEBUG_POLL_AND_WAKE || DEBUG_CALLBACKS
+                LOGD("%p ~ pollOnce - sending message: handler=%p, what=%d",
+                        this, handler.get(), message.what);
+#endif
+                handler->handleMessage(message);
+            } // release handler
+
+            mLock.lock();
+            mSendingMessage = false;
+            result = ALOOPER_POLL_CALLBACK;
+        } else {
+            // The last message left at the head of the queue determines the next wakeup time.
+            mNextMessageUptime = messageEnvelope.uptime;
+            break;
+        }
+    }
+
+    // Release lock.
+    mLock.unlock();
+
+    // Invoke all response callbacks.
     for (size_t i = 0; i < mResponses.size(); i++) {
         const Response& response = mResponses.itemAt(i);
-        if (response.request.callback) {
+        ALooper_callbackFunc callback = response.request.callback;
+        if (callback) {
+            int fd = response.request.fd;
+            int events = response.events;
+            void* data = response.request.data;
 #if DEBUG_POLL_AND_WAKE || DEBUG_CALLBACKS
-            LOGD("%p ~ pollOnce - invoking callback: fd=%d, events=0x%x, data=%p", this,
-                    response.request.fd, response.events, response.request.data);
+            LOGD("%p ~ pollOnce - invoking fd event callback %p: fd=%d, events=0x%x, data=%p",
+                    this, callback, fd, events, data);
 #endif
-            int callbackResult = response.request.callback(
-                    response.request.fd, response.events, response.request.data);
+            int callbackResult = callback(fd, events, data);
             if (callbackResult == 0) {
-                removeFd(response.request.fd);
+                removeFd(fd);
             }
-
             result = ALOOPER_POLL_CALLBACK;
         }
     }
@@ -593,4 +666,83 @@
 }
 #endif
 
+void Looper::sendMessage(const sp<MessageHandler>& handler, const Message& message) {
+    sendMessageAtTime(LLONG_MIN, handler, message);
+}
+
+void Looper::sendMessageDelayed(nsecs_t uptimeDelay, const sp<MessageHandler>& handler,
+        const Message& message) {
+    nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+    sendMessageAtTime(now + uptimeDelay, handler, message);
+}
+
+void Looper::sendMessageAtTime(nsecs_t uptime, const sp<MessageHandler>& handler,
+        const Message& message) {
+#if DEBUG_CALLBACKS
+    LOGD("%p ~ sendMessageAtTime - uptime=%lld, handler=%p, what=%d",
+            this, uptime, handler.get(), message.what);
+#endif
+
+    size_t i = 0;
+    { // acquire lock
+        AutoMutex _l(mLock);
+
+        size_t messageCount = mMessageEnvelopes.size();
+        while (i < messageCount && uptime >= mMessageEnvelopes.itemAt(i).uptime) {
+            i += 1;
+        }
+
+        MessageEnvelope messageEnvelope(uptime, handler, message);
+        mMessageEnvelopes.insertAt(messageEnvelope, i, 1);
+
+        // Optimization: If the Looper is currently sending a message, then we can skip
+        // the call to wake() because the next thing the Looper will do after processing
+        // messages is to decide when the next wakeup time should be.  In fact, it does
+        // not even matter whether this code is running on the Looper thread.
+        if (mSendingMessage) {
+            return;
+        }
+    } // release lock
+
+    // Wake the poll loop only when we enqueue a new message at the head.
+    if (i == 0) {
+        wake();
+    }
+}
+
+void Looper::removeMessages(const sp<MessageHandler>& handler) {
+#if DEBUG_CALLBACKS
+    LOGD("%p ~ removeMessages - handler=%p", this, handler.get());
+#endif
+
+    { // acquire lock
+        AutoMutex _l(mLock);
+
+        for (size_t i = mMessageEnvelopes.size(); i != 0; ) {
+            const MessageEnvelope& messageEnvelope = mMessageEnvelopes.itemAt(--i);
+            if (messageEnvelope.handler == handler) {
+                mMessageEnvelopes.removeAt(i);
+            }
+        }
+    } // release lock
+}
+
+void Looper::removeMessages(const sp<MessageHandler>& handler, int what) {
+#if DEBUG_CALLBACKS
+    LOGD("%p ~ removeMessages - handler=%p, what=%d", this, handler.get(), what);
+#endif
+
+    { // acquire lock
+        AutoMutex _l(mLock);
+
+        for (size_t i = mMessageEnvelopes.size(); i != 0; ) {
+            const MessageEnvelope& messageEnvelope = mMessageEnvelopes.itemAt(--i);
+            if (messageEnvelope.handler == handler
+                    && messageEnvelope.message.what == what) {
+                mMessageEnvelopes.removeAt(i);
+            }
+        }
+    } // release lock
+}
+
 } // namespace android
diff --git a/libs/utils/tests/Looper_test.cpp b/libs/utils/tests/Looper_test.cpp
index cea1313..8bf2ba2 100644
--- a/libs/utils/tests/Looper_test.cpp
+++ b/libs/utils/tests/Looper_test.cpp
@@ -16,6 +16,13 @@
 
 namespace android {
 
+enum {
+    MSG_TEST1 = 1,
+    MSG_TEST2 = 2,
+    MSG_TEST3 = 3,
+    MSG_TEST4 = 4,
+};
+
 class DelayedWake : public DelayedTask {
     sp<Looper> mLooper;
 
@@ -82,6 +89,15 @@
     }
 };
 
+class StubMessageHandler : public MessageHandler {
+public:
+    Vector<Message> messages;
+
+    virtual void handleMessage(const Message& message) {
+        messages.push(message);
+    }
+};
+
 class LooperTest : public testing::Test {
 protected:
     sp<Looper> mLooper;
@@ -421,5 +437,257 @@
             << "replacement handler callback should be invoked";
 }
 
+TEST_F(LooperTest, SendMessage_WhenOneMessageIsEnqueue_ShouldInvokeHandlerDuringNextPoll) {
+    sp<StubMessageHandler> handler = new StubMessageHandler();
+    mLooper->sendMessage(handler, Message(MSG_TEST1));
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(100);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "elapsed time should approx. zero because message was already sent";
+    EXPECT_EQ(ALOOPER_POLL_CALLBACK, result)
+            << "pollOnce result should be ALOOPER_POLL_CALLBACK because message was sent";
+    EXPECT_EQ(size_t(1), handler->messages.size())
+            << "handled message";
+    EXPECT_EQ(MSG_TEST1, handler->messages[0].what)
+            << "handled message";
+}
+
+TEST_F(LooperTest, SendMessage_WhenMultipleMessagesAreEnqueued_ShouldInvokeHandlersInOrderDuringNextPoll) {
+    sp<StubMessageHandler> handler1 = new StubMessageHandler();
+    sp<StubMessageHandler> handler2 = new StubMessageHandler();
+    mLooper->sendMessage(handler1, Message(MSG_TEST1));
+    mLooper->sendMessage(handler2, Message(MSG_TEST2));
+    mLooper->sendMessage(handler1, Message(MSG_TEST3));
+    mLooper->sendMessage(handler1, Message(MSG_TEST4));
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(1000);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "elapsed time should approx. zero because message was already sent";
+    EXPECT_EQ(ALOOPER_POLL_CALLBACK, result)
+            << "pollOnce result should be ALOOPER_POLL_CALLBACK because message was sent";
+    EXPECT_EQ(size_t(3), handler1->messages.size())
+            << "handled message";
+    EXPECT_EQ(MSG_TEST1, handler1->messages[0].what)
+            << "handled message";
+    EXPECT_EQ(MSG_TEST3, handler1->messages[1].what)
+            << "handled message";
+    EXPECT_EQ(MSG_TEST4, handler1->messages[2].what)
+            << "handled message";
+    EXPECT_EQ(size_t(1), handler2->messages.size())
+            << "handled message";
+    EXPECT_EQ(MSG_TEST2, handler2->messages[0].what)
+            << "handled message";
+}
+
+TEST_F(LooperTest, SendMessageDelayed_WhenSentToTheFuture_ShouldInvokeHandlerAfterDelayTime) {
+    sp<StubMessageHandler> handler = new StubMessageHandler();
+    mLooper->sendMessageDelayed(ms2ns(100), handler, Message(MSG_TEST1));
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(1000);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "first poll should end quickly because next message timeout was computed";
+    EXPECT_EQ(ALOOPER_POLL_WAKE, result)
+            << "pollOnce result should be ALOOPER_POLL_WAKE due to wakeup";
+    EXPECT_EQ(size_t(0), handler->messages.size())
+            << "no message handled yet";
+
+    result = mLooper->pollOnce(1000);
+    elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_EQ(size_t(1), handler->messages.size())
+            << "handled message";
+    EXPECT_EQ(MSG_TEST1, handler->messages[0].what)
+            << "handled message";
+    EXPECT_NEAR(100, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "second poll should end around the time of the delayed message dispatch";
+    EXPECT_EQ(ALOOPER_POLL_CALLBACK, result)
+            << "pollOnce result should be ALOOPER_POLL_CALLBACK because message was sent";
+
+    result = mLooper->pollOnce(100);
+    elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(100 + 100, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "third poll should timeout";
+    EXPECT_EQ(ALOOPER_POLL_TIMEOUT, result)
+            << "pollOnce result should be ALOOPER_POLL_TIMEOUT because there were no messages left";
+}
+
+TEST_F(LooperTest, SendMessageDelayed_WhenSentToThePast_ShouldInvokeHandlerDuringNextPoll) {
+    sp<StubMessageHandler> handler = new StubMessageHandler();
+    mLooper->sendMessageDelayed(ms2ns(-1000), handler, Message(MSG_TEST1));
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(100);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "elapsed time should approx. zero because message was already sent";
+    EXPECT_EQ(ALOOPER_POLL_CALLBACK, result)
+            << "pollOnce result should be ALOOPER_POLL_CALLBACK because message was sent";
+    EXPECT_EQ(size_t(1), handler->messages.size())
+            << "handled message";
+    EXPECT_EQ(MSG_TEST1, handler->messages[0].what)
+            << "handled message";
+}
+
+TEST_F(LooperTest, SendMessageDelayed_WhenSentToThePresent_ShouldInvokeHandlerDuringNextPoll) {
+    sp<StubMessageHandler> handler = new StubMessageHandler();
+    mLooper->sendMessageDelayed(0, handler, Message(MSG_TEST1));
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(100);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "elapsed time should approx. zero because message was already sent";
+    EXPECT_EQ(ALOOPER_POLL_CALLBACK, result)
+            << "pollOnce result should be ALOOPER_POLL_CALLBACK because message was sent";
+    EXPECT_EQ(size_t(1), handler->messages.size())
+            << "handled message";
+    EXPECT_EQ(MSG_TEST1, handler->messages[0].what)
+            << "handled message";
+}
+
+TEST_F(LooperTest, SendMessageAtTime_WhenSentToTheFuture_ShouldInvokeHandlerAfterDelayTime) {
+    nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+    sp<StubMessageHandler> handler = new StubMessageHandler();
+    mLooper->sendMessageAtTime(now + ms2ns(100), handler, Message(MSG_TEST1));
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(1000);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "first poll should end quickly because next message timeout was computed";
+    EXPECT_EQ(ALOOPER_POLL_WAKE, result)
+            << "pollOnce result should be ALOOPER_POLL_WAKE due to wakeup";
+    EXPECT_EQ(size_t(0), handler->messages.size())
+            << "no message handled yet";
+
+    result = mLooper->pollOnce(1000);
+    elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_EQ(size_t(1), handler->messages.size())
+            << "handled message";
+    EXPECT_EQ(MSG_TEST1, handler->messages[0].what)
+            << "handled message";
+    EXPECT_NEAR(100, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "second poll should end around the time of the delayed message dispatch";
+    EXPECT_EQ(ALOOPER_POLL_CALLBACK, result)
+            << "pollOnce result should be ALOOPER_POLL_CALLBACK because message was sent";
+
+    result = mLooper->pollOnce(100);
+    elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(100 + 100, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "third poll should timeout";
+    EXPECT_EQ(ALOOPER_POLL_TIMEOUT, result)
+            << "pollOnce result should be ALOOPER_POLL_TIMEOUT because there were no messages left";
+}
+
+TEST_F(LooperTest, SendMessageAtTime_WhenSentToThePast_ShouldInvokeHandlerDuringNextPoll) {
+    nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+    sp<StubMessageHandler> handler = new StubMessageHandler();
+    mLooper->sendMessageAtTime(now - ms2ns(1000), handler, Message(MSG_TEST1));
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(100);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "elapsed time should approx. zero because message was already sent";
+    EXPECT_EQ(ALOOPER_POLL_CALLBACK, result)
+            << "pollOnce result should be ALOOPER_POLL_CALLBACK because message was sent";
+    EXPECT_EQ(size_t(1), handler->messages.size())
+            << "handled message";
+    EXPECT_EQ(MSG_TEST1, handler->messages[0].what)
+            << "handled message";
+}
+
+TEST_F(LooperTest, SendMessageAtTime_WhenSentToThePresent_ShouldInvokeHandlerDuringNextPoll) {
+    nsecs_t now = systemTime(SYSTEM_TIME_MONOTONIC);
+    sp<StubMessageHandler> handler = new StubMessageHandler();
+    mLooper->sendMessageAtTime(now, handler, Message(MSG_TEST1));
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(100);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "elapsed time should approx. zero because message was already sent";
+    EXPECT_EQ(ALOOPER_POLL_CALLBACK, result)
+            << "pollOnce result should be ALOOPER_POLL_CALLBACK because message was sent";
+    EXPECT_EQ(size_t(1), handler->messages.size())
+            << "handled message";
+    EXPECT_EQ(MSG_TEST1, handler->messages[0].what)
+            << "handled message";
+}
+
+TEST_F(LooperTest, RemoveMessage_WhenRemovingAllMessagesForHandler_ShouldRemoveThoseMessage) {
+    sp<StubMessageHandler> handler = new StubMessageHandler();
+    mLooper->sendMessage(handler, Message(MSG_TEST1));
+    mLooper->sendMessage(handler, Message(MSG_TEST2));
+    mLooper->sendMessage(handler, Message(MSG_TEST3));
+    mLooper->removeMessages(handler);
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(0);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "elapsed time should approx. zero because message was sent so looper was awoken";
+    EXPECT_EQ(ALOOPER_POLL_WAKE, result)
+            << "pollOnce result should be ALOOPER_POLL_WAKE because looper was awoken";
+    EXPECT_EQ(size_t(0), handler->messages.size())
+            << "no messages to handle";
+
+    result = mLooper->pollOnce(0);
+
+    EXPECT_EQ(ALOOPER_POLL_TIMEOUT, result)
+            << "pollOnce result should be ALOOPER_POLL_TIMEOUT because there was nothing to do";
+    EXPECT_EQ(size_t(0), handler->messages.size())
+            << "no messages to handle";
+}
+
+TEST_F(LooperTest, RemoveMessage_WhenRemovingSomeMessagesForHandler_ShouldRemoveThoseMessage) {
+    sp<StubMessageHandler> handler = new StubMessageHandler();
+    mLooper->sendMessage(handler, Message(MSG_TEST1));
+    mLooper->sendMessage(handler, Message(MSG_TEST2));
+    mLooper->sendMessage(handler, Message(MSG_TEST3));
+    mLooper->sendMessage(handler, Message(MSG_TEST4));
+    mLooper->removeMessages(handler, MSG_TEST3);
+    mLooper->removeMessages(handler, MSG_TEST1);
+
+    StopWatch stopWatch("pollOnce");
+    int result = mLooper->pollOnce(0);
+    int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
+
+    EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
+            << "elapsed time should approx. zero because message was sent so looper was awoken";
+    EXPECT_EQ(ALOOPER_POLL_CALLBACK, result)
+            << "pollOnce result should be ALOOPER_POLL_CALLBACK because two messages were sent";
+    EXPECT_EQ(size_t(2), handler->messages.size())
+            << "no messages to handle";
+    EXPECT_EQ(MSG_TEST2, handler->messages[0].what)
+            << "handled message";
+    EXPECT_EQ(MSG_TEST4, handler->messages[1].what)
+            << "handled message";
+
+    result = mLooper->pollOnce(0);
+
+    EXPECT_EQ(ALOOPER_POLL_TIMEOUT, result)
+            << "pollOnce result should be ALOOPER_POLL_TIMEOUT because there was nothing to do";
+    EXPECT_EQ(size_t(2), handler->messages.size())
+            << "no more messages to handle";
+}
 
 } // namespace android
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 40882d8..554fa43 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -2150,8 +2150,8 @@
     sh = (!sh) ? hw_h : sh;
     const size_t size = sw * sh * 4;
 
-    LOGD("screenshot: sw=%d, sh=%d, minZ=%d, maxZ=%d",
-            sw, sh, minLayerZ, maxLayerZ);
+    //LOGD("screenshot: sw=%d, sh=%d, minZ=%d, maxZ=%d",
+    //        sw, sh, minLayerZ, maxLayerZ);
 
     // make sure to clear all GL error flags
     while ( glGetError() != GL_NO_ERROR ) ;
@@ -2236,7 +2236,7 @@
 
     hw.compositionComplete();
 
-    LOGD("screenshot: result = %s", result<0 ? strerror(result) : "OK");
+    // LOGD("screenshot: result = %s", result<0 ? strerror(result) : "OK");
 
     return result;
 }