Move bounds to GrBatch

BUG=skia:

Review URL: https://codereview.chromium.org/1121463002
diff --git a/src/gpu/GrTessellatingPathRenderer.cpp b/src/gpu/GrTessellatingPathRenderer.cpp
index e00792e..7a9c5a7 100644
--- a/src/gpu/GrTessellatingPathRenderer.cpp
+++ b/src/gpu/GrTessellatingPathRenderer.cpp
@@ -1485,6 +1485,9 @@
       , fViewMatrix(viewMatrix)
       , fClipBounds(clipBounds) {
         this->initClassID<TessellatingPathBatch>();
+
+        fBounds = path.getBounds();
+        viewMatrix.mapRect(&fBounds);
     }
 
     GrColor        fColor;