resolved conflicts for merge of a51a0901 to lmp-mr1-dev-plus-aosp

Change-Id: Id7df835f0bd3d5d276b162635ddfb7fe0918dfed
diff --git a/libs/hwui/renderthread/CanvasContext.cpp b/libs/hwui/renderthread/CanvasContext.cpp
index 6fdf65e6..5aeecd2 100644
--- a/libs/hwui/renderthread/CanvasContext.cpp
+++ b/libs/hwui/renderthread/CanvasContext.cpp
@@ -123,8 +123,8 @@
     setSurface(window);
 }
 
-void CanvasContext::pauseSurface(ANativeWindow* /* window */) {
-    stopDrawing();
+bool CanvasContext::pauseSurface(ANativeWindow* /* window */) {
+    return mRenderThread.removeFrameCallback(this);
 }
 
 // TODO: don't pass viewport size, it's automatic via EGL