Add fixed raster scale use counter histograms.

cc/proto/layer.proto

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 syntax = "proto2";
 
 import "layer_position_constraint.proto";
 import "point3f.proto";
 import "pointf.proto";
 import "recording_source.proto";
@@ skipping 105 matching lines @@
 
   optional int32 scroll_parent_id = 40;
   repeated int32 scroll_children_ids = 41;
 
   optional int32 clip_parent_id = 42;
   repeated int32 clip_children_ids = 43;
 
   optional ScrollOffset scroll_offset = 44;
 
   optional Rect update_rect = 46;
+  optional bool has_will_change_transform_hint = 48;

[danakj, 2016/05/10 22:05:30]

move up with other simple properties. line 112?

[vmpstr, 2016/05/13 00:13:34]

I kind of prefer if this file's fields remained in numerical order, but I can
see that it's not that already... Done and filed a bug to fix all of this. 

 
   // TODO(nyquist): Figure out what to do with LayerAnimationController.
-  // optional LayerAnimationController layer_animation_controller = 48;
-
-  // TODO(nyquist): Figure out what to do with FrameTimingRequests.
-  // repeated FrameTimingRequest frame_timing_requests = 49;
+  // optional LayerAnimationController layer_animation_controller = ???;
 }
 
 message PictureLayerProperties {
   optional RecordingSource recording_source = 1;
   optional Region invalidation = 2;
   optional Rect last_updated_visible_layer_rect = 3;
   optional bool is_mask = 4;
   optional bool nearest_neighbor = 5;
 
   optional int64 update_source_frame_number = 6;
 }
 
 message SolidColorScrollbarLayerProperties {
   enum ScrollbarOrientation {
     HORIZONTAL = 0;
     VERTICAL = 1;
   };
 
   optional int32 scroll_layer_id = 1;
   optional int32 thumb_thickness = 2;
   optional int32 track_start = 3;
   optional bool is_left_side_vertical_scrollbar = 4;
   optional ScrollbarOrientation orientation = 5;
 }