Fix drag and drop (2/3)

Handle InputWindowCommands in SurfaceFlinger. Send transferTouchFocus from
SurfaceFlinger to InputFlinger.

Test: InputSurfacesTest.transfer_touch_focus
Bug: 120463595
Change-Id: I6592cc9ee4a77700ea191fd1ca337b91895b61fe
diff --git a/libs/gui/tests/EndToEndNativeInputTest.cpp b/libs/gui/tests/EndToEndNativeInputTest.cpp
index 60542bd..7fc69ff 100644
--- a/libs/gui/tests/EndToEndNativeInputTest.cpp
+++ b/libs/gui/tests/EndToEndNativeInputTest.cpp
@@ -133,6 +133,27 @@
         EXPECT_EQ(AMOTION_EVENT_ACTION_UP, mev->getAction());
     }
 
+    void expectMotionEvent(int motionEventType, int x, int y) {
+        InputEvent *ev = consumeEvent();
+        ASSERT_NE(ev, nullptr);
+        ASSERT_EQ(ev->getType(), AINPUT_EVENT_TYPE_MOTION);
+        MotionEvent *mev = static_cast<MotionEvent *>(ev);
+        EXPECT_EQ(motionEventType, mev->getAction());
+        EXPECT_EQ(x, mev->getX(0));
+        EXPECT_EQ(y, mev->getY(0));
+    }
+
+    void expectNoMotionEvent(int motionEventType) {
+        InputEvent *ev = consumeEvent();
+        if (ev == nullptr || ev->getType() != AINPUT_EVENT_TYPE_MOTION) {
+            // Didn't find an event or a motion event so assume action didn't occur.
+            return;
+        }
+
+        MotionEvent *mev = static_cast<MotionEvent *>(ev);
+        EXPECT_NE(motionEventType, mev->getAction());
+    }
+
     ~InputSurface() {
         mInputFlinger->unregisterInputChannel(mServerChannel);
     }
@@ -255,6 +276,15 @@
     }
 }
 
+void injectMotionEvent(std::string event, int x, int y) {
+    char *buf1, *buf2;
+    asprintf(&buf1, "%d", x);
+    asprintf(&buf2, "%d", y);
+    if (fork() == 0) {
+        execlp("input", "input", "motionevent", event.c_str(), buf1, buf2, NULL);
+    }
+}
+
 TEST_F(InputSurfacesTest, can_receive_input) {
     std::unique_ptr<InputSurface> surface = makeSurface(100, 100);
     surface->showAt(100, 100);
@@ -439,5 +469,25 @@
     injectTap(11, 11);
     bgSurface->expectTap(1, 1);
 }
+
+TEST_F(InputSurfacesTest, transfer_touch_focus) {
+    std::unique_ptr<InputSurface> fromSurface = makeSurface(100, 100);
+
+    fromSurface->showAt(10, 10);
+    injectMotionEvent("DOWN", 11, 11);
+    fromSurface->expectMotionEvent(AMOTION_EVENT_ACTION_DOWN, 1, 1);
+
+    std::unique_ptr<InputSurface> toSurface = makeSurface(100, 100);
+    toSurface->showAt(10, 10);
+
+    sp<IBinder> fromToken = fromSurface->mServerChannel->getToken();
+    sp<IBinder> toToken = toSurface->mServerChannel->getToken();
+    SurfaceComposerClient::Transaction t;
+    t.transferTouchFocus(fromToken, toToken).apply(true);
+
+    injectMotionEvent("UP", 11, 11);
+    toSurface->expectMotionEvent(AMOTION_EVENT_ACTION_UP, 1, 1);
+    fromSurface->expectNoMotionEvent(AMOTION_EVENT_ACTION_UP);
+}
 }
 }