Fix clipping and stencil layer issues

bug:8235699

Ensure rectangle clipping operations disable deferring when necessary
(i.e., when the op might create a non-rect region), including in
DisplayList::setViewProperties

Additionally, makes clipping with a kUnion always use a region, for
consistency with software rendering

Change-Id: I6730f1a80250bcf3f91cd4afde646d470a12dbc2
diff --git a/libs/hwui/OpenGLRenderer.h b/libs/hwui/OpenGLRenderer.h
index e12083c..80f2081 100644
--- a/libs/hwui/OpenGLRenderer.h
+++ b/libs/hwui/OpenGLRenderer.h
@@ -198,6 +198,7 @@
     virtual void scale(float sx, float sy);
     virtual void skew(float sx, float sy);
 
+    bool hasRectToRectTransform();
     ANDROID_API void getMatrix(SkMatrix* matrix);
     virtual void setMatrix(SkMatrix* matrix);
     virtual void concatMatrix(SkMatrix* matrix);