Eliminate recents upload jank

Bug: 30342017

Upload recents thumbnails in the
dead gaps between frames instead of
at the start of a frame. This eliminates
jank caused by the large texture
upload.

Change-Id: I507cd286d199109c7a9a1511d68ba5ab5d28069f
diff --git a/libs/hwui/renderthread/RenderProxy.h b/libs/hwui/renderthread/RenderProxy.h
index e31062c8..bb111bd 100644
--- a/libs/hwui/renderthread/RenderProxy.h
+++ b/libs/hwui/renderthread/RenderProxy.h
@@ -129,6 +129,7 @@
     ANDROID_API long getDroppedFrameReportCount();
 
     ANDROID_API static int copySurfaceInto(sp<Surface>& surface, SkBitmap* bitmap);
+    ANDROID_API static void prepareToDraw(const SkBitmap& bitmap);
 
 private:
     RenderThread& mRenderThread;