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.cpp b/libs/hwui/renderthread/RenderProxy.cpp
index cc87241..d15fa39 100644
--- a/libs/hwui/renderthread/RenderProxy.cpp
+++ b/libs/hwui/renderthread/RenderProxy.cpp
@@ -293,11 +293,11 @@
     return (void*) success;
 }
 
-bool RenderProxy::copyLayerInto(DeferredLayerUpdater* layer, SkBitmap* bitmap) {
+bool RenderProxy::copyLayerInto(DeferredLayerUpdater* layer, SkBitmap& bitmap) {
     SETUP_TASK(copyLayerInto);
     args->context = mContext;
     args->layer = layer;
-    args->bitmap = bitmap;
+    args->bitmap = &bitmap;
     return (bool) postAndWait(task);
 }