Remove confusing behavior of Rect::intersect() and rename

bug:24670525

Removes silly 'do nothing if rects do not intersect' behavior, and
changes the name to clarify the difference (contrasting against
SkRect::intersect())

bug:24670525

Change-Id: Id2ca1cfea1a9d720d4dc70b251f426d9916f8b53
diff --git a/libs/hwui/RenderProperties.h b/libs/hwui/RenderProperties.h
index 71589c8..f824cc0 100644
--- a/libs/hwui/RenderProperties.h
+++ b/libs/hwui/RenderProperties.h
@@ -549,7 +549,7 @@
         if (flags & CLIP_TO_BOUNDS) {
             outRect->set(0, 0, getWidth(), getHeight());
             if (flags & CLIP_TO_CLIP_BOUNDS) {
-                outRect->intersect(mPrimitiveFields.mClipBounds);
+                outRect->doIntersect(mPrimitiveFields.mClipBounds);
             }
         } else {
             outRect->set(mPrimitiveFields.mClipBounds);