A bunch more cleanups

Switch a few places to using android::canvas
instead of SkCanvas as well which eliminated
some JNI

Change-Id: I8f98b56442a06362b82b984cd1bd3a92398d8dbc
diff --git a/libs/hwui/renderthread/RenderProxy.h b/libs/hwui/renderthread/RenderProxy.h
index 29c6f08..cc475fa 100644
--- a/libs/hwui/renderthread/RenderProxy.h
+++ b/libs/hwui/renderthread/RenderProxy.h
@@ -83,7 +83,7 @@
 
     ANDROID_API DeferredLayerUpdater* createTextureLayer();
     ANDROID_API void buildLayer(RenderNode* node);
-    ANDROID_API bool copyLayerInto(DeferredLayerUpdater* layer, SkBitmap* bitmap);
+    ANDROID_API bool copyLayerInto(DeferredLayerUpdater* layer, SkBitmap& bitmap);
     ANDROID_API void pushLayerUpdate(DeferredLayerUpdater* layer);
     ANDROID_API void cancelLayerUpdate(DeferredLayerUpdater* layer);
     ANDROID_API void detachSurfaceTexture(DeferredLayerUpdater* layer);