Mac: Always use surfaceless mode

content/common/gpu/image_transport_surface_calayer_mac.h

-// Copyright 2014 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.
-
-#ifndef CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_CALAYER_MAC_H_
-#define CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_CALAYER_MAC_H_
-
-#include "base/mac/scoped_nsobject.h"
-#include "content/common/gpu/image_transport_surface_fbo_mac.h"
-#include "ui/base/cocoa/remote_layer_api.h"
-#include "ui/gl/gpu_switching_observer.h"
-#include "ui/gl/scoped_cgl.h"
-
-@class ImageTransportCAOpenGLLayer;
-@class ImageTransportIOSurface;
-
-namespace content {
-
-// Allocate CAOpenGLLayer-backed storage for an FBO image transport surface.
-class CALayerStorageProvider
-    : public ImageTransportSurfaceFBO::StorageProvider,
-      public ui::GpuSwitchingObserver {
- public:
-  CALayerStorageProvider(ImageTransportSurfaceFBO* transport_surface);
-  ~CALayerStorageProvider() override;
-
-  // ImageTransportSurfaceFBO::StorageProvider implementation:
-  gfx::Size GetRoundedSize(gfx::Size size) override;
-  bool AllocateColorBufferStorage(
-      CGLContextObj context, const base::Closure& context_dirtied_callback,
-      GLuint texture, gfx::Size pixel_size, float scale_factor) override;
-  void FreeColorBufferStorage() override;
-  void FrameSizeChanged(
-      const gfx::Size& pixel_size, float scale_factor) override;
-  void SwapBuffers(const gfx::Rect& dirty_rect) override;
-  void WillWriteToBackbuffer() override;
-  void DiscardBackbuffer() override;
-  void SwapBuffersAckedByBrowser(bool disable_throttling) override;
-
-  // Interface to the CALayer.
-  CGLContextObj LayerShareGroupContext();
-  base::Closure LayerShareGroupContextDirtiedCallback();
-  bool LayerHasPendingDraw() const;
-  void LayerDoDraw(const gfx::Rect& dirty_rect, bool flipped);
-  void LayerUnblockBrowserIfNeeded();
-  CAContext* LayerCAContext() { return context_.get(); }
-
-  // ui::GpuSwitchingObserver implementation.
-  void OnGpuSwitched() override;
-
- private:
-  void CreateLayerAndRequestDraw(bool should_draw_immediately,
-                                 const gfx::Rect& dirty_rect);
-  void DrawImmediatelyAndUnblockBrowser();
-
-  // The browser will be blocked while there is a frame that was sent to it but
-  // hasn't drawn yet. This call will un-block the browser.
-  void UnblockBrowserIfNeeded();
-
-  // Inform the layer that it is no longer being used, and reset the layer.
-  void ResetLayer();
-
-  ImageTransportSurfaceFBO* transport_surface_;
-
-  // Used to determine if we should use setNeedsDisplay or setAsynchronous to
-  // animate. If vsync is disabled, an immediate setNeedsDisplay and
-  // displayIfNeeded are called.
-  const bool gpu_vsync_disabled_;
-
-  // Used also to determine if we should wait for CoreAnimation to call our
-  // drawInCGLContext, or if we should force it with displayIfNeeded.
-  bool throttling_disabled_;
-
-  // Set when a new swap occurs, and un-set when the frame is acked to the
-  // browser. This is when the CAOpenGLLayer draws or when then IOSurface
-  // is committed.
-  bool has_pending_ack_;
-
-  // The texture with the pixels to draw, and the share group it is allocated
-  // in.
-  base::ScopedTypeRef<CGLContextObj> share_group_context_;
-  base::Closure share_group_context_dirtied_callback_;
-  GLuint fbo_texture_;
-  gfx::Size fbo_pixel_size_;
-  float fbo_scale_factor_;
-
-  // State for the Core Profile code path.
-  GLuint program_;
-  GLuint vertex_shader_;
-  GLuint fragment_shader_;
-  GLuint position_location_;
-  GLuint tex_location_;
-  GLuint vertex_buffer_;
-  GLuint vertex_array_;
-
-  // The CALayer that the current frame is being drawn into.
-  base::scoped_nsobject<CAContext> context_;
-  base::scoped_nsobject<ImageTransportCAOpenGLLayer> ca_opengl_layer_;
-
-  // When a CAContext is destroyed in the GPU process, it will become a blank
-  // CALayer in the browser process. Put retains on these contexts in this queue
-  // when they are discarded, and remove one item from the queue as each frame
-  // is acked.
-  std::list<base::scoped_nsobject<CAContext>> previously_discarded_contexts_;
-
-  // Indicates that the CALayer should be recreated at the next swap. This is
-  // to ensure that the CGLContext created for the CALayer be on the right GPU.
-  bool recreate_layer_after_gpu_switch_;
-
-  // Weak factory against which a timeout task for forcing a draw is created.
-  base::WeakPtrFactory<CALayerStorageProvider> pending_draw_weak_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(CALayerStorageProvider);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_CALAYER_MAC_H_