Revert of Mac Overlays: Add GPU back-pressure (patchset chromium#8 id…

…:140001 of https://codereview.chromium.org/1273563002/ )

Reason for revert:
This broke the WebGL 2.0 prototype on Mac OS -- please see https://code.google.com/p/chromium/issues/detail?id=515696#c16 for details.

Original issue's description:
> Mac Overlays: Add GPU back-pressure
>
> Issue a GL fence after every SwapBuffers. Do not call -[CALayer
> setContents:] with the content being rendered by that SwapBuffers until
> the fence has passed.
>
> Query the previous's frame's GL fence at the beginning of each
> SwapBuffers. Also issue a callback to query the GL fence at the
> mid-point of the VSync period (if there is no subsequent SwapBuffers,
> or if the frame takes more than one VSync to render).
>
> Note that waiting for the GL fence to complete before calling -[CALayer
> setContents] is not required for correctness -- only the expected content
> (everything before the glFlush) will appear in the layer. Rather, the
> reason for waiting for the GL fence is to make the time at which the
> content will appear on-screen more reliable.
>
> Because there may be multiple calls to SwapBuffers in flight, store the
> data necessary to call -[CALayer setContents] in a PendingSwap
> structure. Maintain a queue of these structures.
>
> Because the ImageTransportSurface does not know anything about the
> VSync period, send the CGDirectDisplayID for the attached display to the
> ImageTransportSurface in the AcceleratedSurfaceMsg_BufferPresented IPC
> (which is where the CGL renderer ID is already communicated). Send this
> information instead of the raw VSync parameters so that the updates to
> all windows on a single display may be coalesced into a single callback
> in the future.
>
> Note that this display is the display that is used for vsync by the
> RenderWidgetHostViewMac, so if vsync is disabled, it will be 0.
>
> Separate gfx::ScopedSetGLToRealGLApi into its own header file to
> simplify header orders.
>
> Access the IOSurface of the GLImageIOSurface directly, rather than
> using its ScheduleOverlayPlane method. This simplifies things
> immediately, in that we can reason about the underlying IOSurface's
> lifetime better than weak pointers to images. It will also simplify
> the implementation of partial swap and multiple overlays.
>
> BUG=515696
>
> Committed: https://crrev.com/5c207cac73c835b5f362670d6b46333dfae1f4c4
> Cr-Commit-Position: refs/heads/master@{#342548}

TBR=dcheng@chromium.org,jbauman@chromium.org,tapted@chromium.org,ccameron@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=515696

Review URL: https://codereview.chromium.org/1280033004

Cr-Commit-Position: refs/heads/master@{#342566}

content/browser/compositor/gpu_surfaceless_browser_compositor_output_surface.cc

@@ -98,9 +98,6 @@ void GpuSurfacelessBrowserCompositorOutputSurface::Reshape(
 void GpuSurfacelessBrowserCompositorOutputSurface::OnSwapBuffersCompleted(
     const std::vector<ui::LatencyInfo>& latency_info,
     gfx::SwapResult result) {
-#if defined(OS_MACOSX)
-  NOTREACHED();
-#else
   if (result == gfx::SwapResult::SWAP_NAK_RECREATE_BUFFERS) {
     // Even through the swap failed, this is a fixable error so we can pretend
     // it succeeded to the rest of the system.
@@ -109,7 +106,6 @@ void GpuSurfacelessBrowserCompositorOutputSurface::OnSwapBuffersCompleted(
   }
   GpuBrowserCompositorOutputSurface::OnSwapBuffersCompleted(latency_info,
                                                             result);
-#endif
 }
 
 #if defined(OS_MACOSX)

content/browser/gpu/gpu_process_host_ui_shim.cc

@@ -308,8 +308,7 @@ void GpuProcessHostUIShim::OnAcceleratedSurfaceBuffersSwapped(
         params.scale_factor,
         params.damage_rect,
         base::Bind(&OnSurfaceDisplayedCallback, params.surface_id),
-        &ack_params.disable_throttling, &ack_params.renderer_id,
-        &ack_params.display_id_for_vsync);
+        &ack_params.disable_throttling, &ack_params.renderer_id);
   }
   Send(new AcceleratedSurfaceMsg_BufferPresented(params.route_id, ack_params));
 }

content/browser/renderer_host/render_widget_host_view_mac.h

@@ -496,7 +496,6 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
   // AcceleratedWidgetMacNSView implementation.
   NSView* AcceleratedWidgetGetNSView() const override;
   bool AcceleratedWidgetShouldIgnoreBackpressure() const override;
-  uint32_t AcceleratedWidgetGetDisplayIDForVSync() const override;
   void AcceleratedWidgetSwapCompleted(
       const std::vector<ui::LatencyInfo>& latency_info) override;
   void AcceleratedWidgetHitError() override;

content/browser/renderer_host/render_widget_host_view_mac.mm

@@ -515,13 +515,6 @@ float FlipYFromRectToScreen(float y, float rect_height) {
   return false;
 }
 
-uint32_t RenderWidgetHostViewMac::AcceleratedWidgetGetDisplayIDForVSync()
-    const {
-  if (display_link_)
-    return display_link_->display_id();
-  return 0;
-}
-
 void RenderWidgetHostViewMac::AcceleratedWidgetSwapCompleted(
     const std::vector<ui::LatencyInfo>& all_latency_info) {
   if (!render_widget_host_)

content/common/gpu/gpu_messages.h

@@ -110,9 +110,6 @@ IPC_STRUCT_BEGIN(AcceleratedSurfaceMsg_BufferPresented_Params)
   // If the browser is drawing to the screen, this is the CGL renderer ID of
   // the GL context that the brower is using.
   IPC_STRUCT_MEMBER(int32, renderer_id)
-  // The CGDirectDisplayID on which the content was displayed, to be used for
-  // computing vsync. If vsync is not enabled, this is zero.
-  IPC_STRUCT_MEMBER(uint32, display_id_for_vsync)
 IPC_STRUCT_END()
 #endif
 

content/common/gpu/image_transport_surface_calayer_mac.mm

@@ -16,9 +16,9 @@
 #include "ui/base/cocoa/animation_utils.h"
 #include "ui/gfx/geometry/dip_util.h"
 #include "ui/gfx/geometry/size_conversions.h"
+#include "ui/gl/gl_gl_api_implementation.h"
 #include "ui/gl/gl_switches.h"
 #include "ui/gl/gpu_switching_manager.h"
-#include "ui/gl/scoped_api.h"
 
 namespace {
 const size_t kFramesToKeepCAContextAfterDiscard = 2;

content/common/gpu/image_transport_surface_overlay_mac.h

@@ -5,13 +5,9 @@
 #ifndef CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_OVERLAY_MAC_H_
 #define CONTENT_COMMON_GPU_IMAGE_TRANSPORT_SURFACE_OVERLAY_MAC_H_
 
-#include <deque>
-
-#include "base/memory/linked_ptr.h"
 #import "base/mac/scoped_nsobject.h"
 #include "content/common/gpu/gpu_command_buffer_stub.h"
 #include "content/common/gpu/image_transport_surface.h"
-#include "ui/accelerated_widget_mac/display_link_mac.h"
 #include "ui/gl/gl_surface.h"
 
 @class CAContext;
@@ -51,35 +47,14 @@ class ImageTransportSurfaceOverlayMac : public gfx::GLSurface,
   void WakeUpGpu() override;
 
  private:
-  class PendingSwap;
-
   ~ImageTransportSurfaceOverlayMac() override;
-
-  gfx::SwapResult SwapBuffersInternal(const gfx::Rect& pixel_damage_rect);
-
-  // Returns true if the front of |pending_swaps_| has completed, or has timed
-  // out by |now|.
-  bool IsFirstPendingSwapReadyToDisplay(
-    const base::TimeTicks& now);
-  // Sets the CALayer contents to the IOSurface for the front of
-  // |pending_swaps_|, and removes it from the queue.
-  void DisplayFirstPendingSwapImmediately();
-  // Force that all of |pending_swaps_| displayed immediately, and the list be
-  // cleared.
-  void FinishAllPendingSwaps();
-  // Callback issued during the next vsync period ofter a SwapBuffers call,
-  // to check if the swap is completed, and display the frame. Note that if
-  // another SwapBuffers happens before this callback, the pending swap will
-  // be tested at that time, too.
-  void CheckPendingSwapsCallback();
-  // Function to post the above callback. The argument |now| is passed as an
-  // argument to avoid redundant calls to base::TimeTicks::Now.
-  void PostCheckPendingSwapsCallbackIfNeeded(const base::TimeTicks& now);
-
   scoped_ptr<ImageTransportHelper> helper_;
   base::scoped_nsobject<CAContext> ca_context_;
   base::scoped_nsobject<CALayer> layer_;
 
+  // A phony NSView handle used to identify this.
+  gfx::AcceleratedWidget widget_;
+
   gfx::Size pixel_size_;
   float scale_factor_;
   std::vector<ui::LatencyInfo> latency_info_;
@@ -88,19 +63,6 @@ class ImageTransportSurfaceOverlayMac : public gfx::GLSurface,
   // consumed and reset when SwapBuffers is called. For now, only one overlay
   // plane is supported.
   gfx::GLImage* pending_overlay_image_;
-
-  // A queue of all frames that have been created by SwapBuffersInternal but
-  // have not yet been displayed. This queue is checked at the beginning of
-  // every swap and also by a callback.
-  std::deque<linked_ptr<PendingSwap>> pending_swaps_;
-
-  // The display link used to compute the time for callbacks.
-  scoped_refptr<ui::DisplayLinkMac> display_link_mac_;
-
-  // True if there is a pending call to CheckPendingSwapsCallback posted.
-  bool has_pending_callback_;
-
-  base::WeakPtrFactory<ImageTransportSurfaceOverlayMac> weak_factory_;
 };
 
 }  // namespace content