Simplify ClipArea to prefer Rect args

Change-Id: I8af83d01dc5dd8009a0cd235dd8b59dab61d8560
diff --git a/libs/hwui/Snapshot.cpp b/libs/hwui/Snapshot.cpp
index 2f535bb..c6d8977 100644
--- a/libs/hwui/Snapshot.cpp
+++ b/libs/hwui/Snapshot.cpp
@@ -88,9 +88,9 @@
     mClipArea->clipRegion(region, op);
 }
 
-void Snapshot::clip(float left, float top, float right, float bottom, SkRegion::Op op) {
+void Snapshot::clip(const Rect& localClip, SkRegion::Op op) {
     flags |= Snapshot::kFlagClipSet;
-    mClipArea->clipRectWithTransform(left, top, right, bottom, transform, op);
+    mClipArea->clipRectWithTransform(localClip, transform, op);
 }
 
 void Snapshot::clipPath(const SkPath& path, SkRegion::Op op) {