Set device scale factor in CompositorFrame and scale frame size in WS.

services/ui/ws/frame_generator.cc

 // Copyright 2016 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 "services/ui/ws/frame_generator.h"
 
 #include <utility>
 
 #include "base/containers/adapters.h"
 #include "cc/output/compositor_frame.h"
@@ skipping 134 matching lines @@
     cc::FilterOperations filters;
     filters.Append(cc::FilterOperation::CreateInvertFilter(1.f));
     quad->SetNew(shared_state, output_rect, output_rect, render_pass_id,
                  0 /* mask_resource_id */, gfx::Vector2dF() /* mask_uv_scale */,
                  gfx::Size() /* mask_texture_size */, filters,
                  gfx::Vector2dF() /* filters_scale */,
                  gfx::PointF() /* filters_origin */,
                  cc::FilterOperations() /* background_filters */);
     frame.render_pass_list.push_back(std::move(invert_pass));
   }
+  frame.metadata.device_scale_factor = device_scale_factor_;
 
   return frame;
 }
 
 void FrameGenerator::DrawWindowTree(
     cc::RenderPass* pass,
     ServerWindow* window,
     const gfx::Vector2d& parent_to_root_origin_offset,
     float opacity) {
   if (!window->visible())
@@ skipping 178 matching lines @@
   cc::SurfaceId underlay_surface_id =
       window->compositor_frame_sink_manager()->GetLatestSurfaceId(
           mojom::CompositorFrameSinkType::UNDERLAY);
   if (underlay_surface_id.is_valid())
     RemoveFrameSinkReference(underlay_surface_id.frame_sink_id());
 }
 
 }  // namespace ws
 
 }  // namespace ui