Remove IME surface when hidden

When IME is no longer shown, notify IMS to hide the window surface.
This reclaims the memory allocated to IME window surface.

Fix: 150163310
Test: atest CtsInputMethodTests
      Manually:
      1. Open any app that has editor  and run
         adb shell  dumpsys SurfaceFlinger | grep Total
      2. Note down total memory
      3. Tap on editor and IME shows. Note down memory
         using command in #1. It should go up by ~27MB
      4. Hide IME and note down memory again.
         It should revert to original value in #1.

Change-Id: I6c2a13dd40b22d3fd62b4763ba369992e5ff1138

1 files changed, 10 insertions, 0 deletions

diff --git a/core/java/android/inputmethodservice/IInputMethodSessionWrapper.java b/core/java/android/inputmethodservice/IInputMethodSessionWrapper.java
index 9327b241c6c5..e9de27456f97 100644
--- a/core/java/android/inputmethodservice/IInputMethodSessionWrapper.java
+++ b/core/java/android/inputmethodservice/IInputMethodSessionWrapper.java
@@ -53,6 +53,7 @@ class IInputMethodSessionWrapper extends IInputMethodSession.Stub
     private static final int DO_FINISH_SESSION = 110;
     private static final int DO_VIEW_CLICKED = 115;
     private static final int DO_NOTIFY_IME_HIDDEN = 120;
+    private static final int DO_REMOVE_IME_SURFACE = 130;
 
     @UnsupportedAppUsage
     HandlerCaller mCaller;
@@ -136,6 +137,10 @@ class IInputMethodSessionWrapper extends IInputMethodSession.Stub
                 mInputMethodSession.notifyImeHidden();
                 return;
             }
+            case DO_REMOVE_IME_SURFACE: {
+                mInputMethodSession.removeImeSurface();
+                return;
+            }
         }
         Log.w(TAG, "Unhandled message code: " + msg.what);
     }
@@ -184,6 +189,11 @@ class IInputMethodSessionWrapper extends IInputMethodSession.Stub
     }
 
     @Override
+    public void removeImeSurface() {
+        mCaller.executeOrSendMessage(mCaller.obtainMessage(DO_REMOVE_IME_SURFACE));
+    }
+
+    @Override
     public void updateCursor(Rect newCursor) {
         mCaller.executeOrSendMessage(
                 mCaller.obtainMessageO(DO_UPDATE_CURSOR, newCursor));