cc: Remove implicit conversions from Rect to RectF in src/cc/.

cc/trees/property_tree_builder.cc

Index: cc/trees/property_tree_builder.cc
diff --git a/cc/trees/property_tree_builder.cc b/cc/trees/property_tree_builder.cc
index 76e12e053888b3066082540b3fcade6ccf2dc1c5..b565d04e0a104749a55f309bb4063228f6e4e702 100644
--- a/cc/trees/property_tree_builder.cc
+++ b/cc/trees/property_tree_builder.cc
@@ -495,7 +495,7 @@ void BuildPropertyTreesTopLevelInternal(
   data_for_recursion.sequence_number = property_trees->sequence_number;
 
   ClipNode root_clip;
-  root_clip.data.clip = viewport;
+  root_clip.data.clip = gfx::RectF(viewport);
   root_clip.data.transform_id = kRootPropertyTreeNodeId;
   data_for_recursion.clip_tree_parent = data_for_recursion.clip_tree->Insert(
       root_clip, kUnclippedRootClipTreeNodeId);