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

content/browser/compositor/mus_browser_compositor_output_surface.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 "content/browser/compositor/mus_browser_compositor_output_surface.h"
 
 #include <utility>
 
 #include "cc/output/compositor_frame.h"
 #include "cc/output/output_surface_frame.h"
 #include "cc/quads/render_pass.h"
 #include "cc/quads/texture_draw_quad.h"
 #include "components/display_compositor/compositor_overlay_candidate_validator.h"
 #include "content/common/gpu/client/context_provider_command_buffer.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
 #include "gpu/ipc/client/command_buffer_proxy_impl.h"
 #include "services/ui/public/cpp/window.h"
 #include "services/ui/public/cpp/window_compositor_frame_sink.h"
 #include "ui/aura/mus/window_compositor_frame_sink.h"
 #include "ui/aura/mus/window_port_mus.h"
 #include "ui/aura/window.h"
+#include "ui/display/screen.h"
 
 namespace content {
 
 MusBrowserCompositorOutputSurface::MusBrowserCompositorOutputSurface(
     ui::Window* window,
     scoped_refptr<ContextProviderCommandBuffer> context,
     gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager,
     const UpdateVSyncParametersCallback& update_vsync_parameters_callback,
     std::unique_ptr<display_compositor::CompositorOverlayCandidateValidator>
         overlay_candidate_validator)
@@ skipping 34 matching lines @@
 
 cc::BeginFrameSource* MusBrowserCompositorOutputSurface::GetBeginFrameSource() {
   return begin_frame_source_;
 }
 
 void MusBrowserCompositorOutputSurface::SwapBuffers(
     cc::OutputSurfaceFrame frame) {
   const gfx::Rect bounds = ui_window_ ? gfx::Rect(ui_window_->bounds().size())
                                       : gfx::Rect(window_->bounds().size());
   cc::CompositorFrame ui_frame;
+  ui_frame.metadata.device_scale_factor = display::Screen::GetScreen()

[danakj, 2016/12/15 18:58:02]

I would normally ask that you plumb this in more directly, but I cant justify
investing much in this impl of OutputSurface which we'll delete ASAP.

[Fady Samuel, 2016/12/15 19:01:00]

+1

+                                              ->GetDisplayNearestWindow(window_)
+                                              .device_scale_factor();
   ui_frame.metadata.latency_info = std::move(frame.latency_info);
   // Reset latency_info to known empty state after moving contents.
   frame.latency_info.clear();
   const int render_pass_id = 1;
   std::unique_ptr<cc::RenderPass> pass = cc::RenderPass::Create();
   const bool has_transparent_background = true;
   pass->SetAll(render_pass_id, bounds, bounds, gfx::Transform(),
                has_transparent_background);
   // The SharedQuadState is owned by the SharedQuadStateList
   // shared_quad_state_list.
@@ skipping 120 matching lines @@
 
 const gpu::Mailbox& MusBrowserCompositorOutputSurface::GetMailboxFromResourceId(
     uint32_t id) {
   DCHECK_LT(id, mailboxes_.size());
   DCHECK(std::find(free_resource_ids_.begin(), free_resource_ids_.end(), id) ==
          free_resource_ids_.end());
   return mailboxes_[id];
 }
 
 }  // namespace content