Divide InputDispatcher into several files.

This CL does:
1) Isolate implementation details of InputDispatcher from outside and
only expose necessary header files;
2) Move implementation details into android::inputdispatcher namespace;
3) Make input dispatcher a static library for inputflinger to link
against;
4) Add InputDispatcherFactory.{h,cpp} to isolate implementation details
in InputDispatcher.h from InputManager.

Bug: 140139676
Test: Touches on touchscreen can be dispatched to right windows.
Change-Id: Ib61c16fd41f3f76f538a3de9b54f31ac304e03a5
diff --git a/services/inputflinger/dispatcher/include/InputDispatcherPolicyInterface.h b/services/inputflinger/dispatcher/include/InputDispatcherPolicyInterface.h
new file mode 100644
index 0000000..4214488
--- /dev/null
+++ b/services/inputflinger/dispatcher/include/InputDispatcherPolicyInterface.h
@@ -0,0 +1,123 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _UI_INPUT_INPUTDISPATCHER_INPUTDISPATCHERPOLICYINTERFACE_H
+#define _UI_INPUT_INPUTDISPATCHER_INPUTDISPATCHERPOLICYINTERFACE_H
+
+#include "InputDispatcherConfiguration.h"
+
+#include <binder/IBinder.h>
+#include <input/Input.h>
+#include <utils/RefBase.h>
+
+namespace android {
+
+class InputApplicationHandle;
+
+/*
+ * Input dispatcher policy interface.
+ *
+ * The input reader policy is used by the input reader to interact with the Window Manager
+ * and other system components.
+ *
+ * The actual implementation is partially supported by callbacks into the DVM
+ * via JNI.  This interface is also mocked in the unit tests.
+ */
+class InputDispatcherPolicyInterface : public virtual RefBase {
+protected:
+    InputDispatcherPolicyInterface() {}
+    virtual ~InputDispatcherPolicyInterface() {}
+
+public:
+    /* Notifies the system that a configuration change has occurred. */
+    virtual void notifyConfigurationChanged(nsecs_t when) = 0;
+
+    /* Notifies the system that an application is not responding.
+     * Returns a new timeout to continue waiting, or 0 to abort dispatch. */
+    virtual nsecs_t notifyANR(const sp<InputApplicationHandle>& inputApplicationHandle,
+                              const sp<IBinder>& token, const std::string& reason) = 0;
+
+    /* Notifies the system that an input channel is unrecoverably broken. */
+    virtual void notifyInputChannelBroken(const sp<IBinder>& token) = 0;
+    virtual void notifyFocusChanged(const sp<IBinder>& oldToken, const sp<IBinder>& newToken) = 0;
+
+    /* Gets the input dispatcher configuration. */
+    virtual void getDispatcherConfiguration(InputDispatcherConfiguration* outConfig) = 0;
+
+    /* Filters an input event.
+     * Return true to dispatch the event unmodified, false to consume the event.
+     * A filter can also transform and inject events later by passing POLICY_FLAG_FILTERED
+     * to injectInputEvent.
+     */
+    virtual bool filterInputEvent(const InputEvent* inputEvent, uint32_t policyFlags) = 0;
+
+    /* Intercepts a key event immediately before queueing it.
+     * The policy can use this method as an opportunity to perform power management functions
+     * and early event preprocessing such as updating policy flags.
+     *
+     * This method is expected to set the POLICY_FLAG_PASS_TO_USER policy flag if the event
+     * should be dispatched to applications.
+     */
+    virtual void interceptKeyBeforeQueueing(const KeyEvent* keyEvent, uint32_t& policyFlags) = 0;
+
+    /* Intercepts a touch, trackball or other motion event before queueing it.
+     * The policy can use this method as an opportunity to perform power management functions
+     * and early event preprocessing such as updating policy flags.
+     *
+     * This method is expected to set the POLICY_FLAG_PASS_TO_USER policy flag if the event
+     * should be dispatched to applications.
+     */
+    virtual void interceptMotionBeforeQueueing(const int32_t displayId, nsecs_t when,
+                                               uint32_t& policyFlags) = 0;
+
+    /* Allows the policy a chance to intercept a key before dispatching. */
+    virtual nsecs_t interceptKeyBeforeDispatching(const sp<IBinder>& token,
+                                                  const KeyEvent* keyEvent,
+                                                  uint32_t policyFlags) = 0;
+
+    /* Allows the policy a chance to perform default processing for an unhandled key.
+     * Returns an alternate keycode to redispatch as a fallback, or 0 to give up. */
+    virtual bool dispatchUnhandledKey(const sp<IBinder>& token, const KeyEvent* keyEvent,
+                                      uint32_t policyFlags, KeyEvent* outFallbackKeyEvent) = 0;
+
+    /* Notifies the policy about switch events.
+     */
+    virtual void notifySwitch(nsecs_t when, uint32_t switchValues, uint32_t switchMask,
+                              uint32_t policyFlags) = 0;
+
+    /* Poke user activity for an event dispatched to a window. */
+    virtual void pokeUserActivity(nsecs_t eventTime, int32_t eventType) = 0;
+
+    /* Checks whether a given application pid/uid has permission to inject input events
+     * into other applications.
+     *
+     * This method is special in that its implementation promises to be non-reentrant and
+     * is safe to call while holding other locks.  (Most other methods make no such guarantees!)
+     */
+    virtual bool checkInjectEventsPermissionNonReentrant(int32_t injectorPid,
+                                                         int32_t injectorUid) = 0;
+
+    /* Notifies the policy that a pointer down event has occurred outside the current focused
+     * window.
+     *
+     * The touchedToken passed as an argument is the window that received the input event.
+     */
+    virtual void onPointerDownOutsideFocus(const sp<IBinder>& touchedToken) = 0;
+};
+
+} // namespace android
+
+#endif // _UI_INPUT_INPUTDISPATCHER_INPUTDISPATCHERPOLICYINTERFACE_H