Implements core logic for Pixel Canvas

ui/compositor/layer.cc

 // Copyright (c) 2012 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.
 
 #include "ui/compositor/layer.h"
 
 #include <algorithm>
 #include <memory>
 #include <utility>
 
@@ skipping 901 matching lines @@
 
 scoped_refptr<cc::DisplayItemList> Layer::PaintContentsToDisplayList(
     ContentLayerClient::PaintingControlSetting painting_control) {
   TRACE_EVENT1("ui", "Layer::PaintContentsToDisplayList", "name", name_);
   gfx::Rect local_bounds(bounds().size());
   gfx::Rect invalidation(
       gfx::IntersectRects(paint_region_.bounds(), local_bounds));
   paint_region_.Clear();
   auto display_list = make_scoped_refptr(new cc::DisplayItemList);
   if (delegate_) {
-    delegate_->OnPaintLayer(
-        PaintContext(display_list.get(), device_scale_factor_, invalidation));
+    display_list->set_pixel_canvas_enabled(
+        base::CommandLine::ForCurrentProcess()->HasSwitch(
+            switches::kEnablePixelCanvasRecording));

[oshima, 2017/06/15 22:59:12]

can you initialize once instead of querying everytime?

[malaykeshav, 2017/06/16 20:41:57]

Done

+    PaintContext context(display_list.get(), device_scale_factor_, invalidation,
+                         size());
+    delegate_->OnPaintLayer(context);
   }
   display_list->Finalize();
   // TODO(domlaskowski): Move mirror invalidation to Layer::SchedulePaint.
   for (const auto& mirror : mirrors_)
     mirror->dest()->SchedulePaint(invalidation);
   return display_list;
 }
 
 bool Layer::FillsBoundsCompletely() const { return fills_bounds_completely_; }
 
@@ skipping 306 matching lines @@
   const auto it = std::find_if(mirrors_.begin(), mirrors_.end(),
       [mirror](const std::unique_ptr<LayerMirror>& mirror_ptr) {
         return mirror_ptr.get() == mirror;
       });
 
   DCHECK(it != mirrors_.end());
   mirrors_.erase(it);
 }
 
 }  // namespace ui