FocusResolver: Clean up focus requests and results when a display is removed

Prevents FocusResolver from leaking focus requests and results as
displays are added and removed.

Test: atest inputflinger_tests
Fixes: 188008394
Change-Id: I635b9becf91056fd540ab9d9546dd67a09324fc6
diff --git a/services/inputflinger/dispatcher/InputDispatcher.h b/services/inputflinger/dispatcher/InputDispatcher.h
index bb3f3e6..9edf41c 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.h
+++ b/services/inputflinger/dispatcher/InputDispatcher.h
@@ -139,6 +139,8 @@
 
     std::array<uint8_t, 32> sign(const VerifiedInputEvent& event) const;
 
+    void displayRemoved(int32_t displayId) override;
+
 private:
     enum class DropReason {
         NOT_DROPPED,
@@ -343,6 +345,9 @@
     std::unordered_map<int32_t, TouchState> mTouchStatesByDisplay GUARDED_BY(mLock);
     std::unique_ptr<DragState> mDragState GUARDED_BY(mLock);
 
+    void setFocusedApplicationLocked(
+            int32_t displayId,
+            const std::shared_ptr<InputApplicationHandle>& inputApplicationHandle) REQUIRES(mLock);
     // Focused applications.
     std::unordered_map<int32_t, std::shared_ptr<InputApplicationHandle>>
             mFocusedApplicationHandlesByDisplay GUARDED_BY(mLock);