NOT for review (for discussion): Query IOSurfaceIsInUse in the browser process

gpu/ipc/service/image_transport_surface_overlay_mac.mm

 // Copyright 2015 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 "gpu/ipc/service/image_transport_surface_overlay_mac.h"
 
 #include <CoreGraphics/CoreGraphics.h>
 #include <IOSurface/IOSurface.h>
 #include <OpenGL/CGLRenderers.h>
 #include <OpenGL/CGLTypes.h>
@@ skipping 148 matching lines @@
       fullscreen_low_power_ca_context_id;
   params.io_surface = io_surface;
   params.pixel_size = size;
   params.scale_factor = scale_factor;
   params.latency_info = std::move(latency_info);
   params.result = gfx::SwapResult::SWAP_ACK;
 
   for (auto& query : ca_layer_in_use_queries_) {
     gpu::TextureInUseResponse response;
     response.texture = query.texture;
-    bool in_use = false;
+    response.in_use_valid = false;
     gl::GLImageIOSurface* io_surface_image =
         gl::GLImageIOSurface::FromGLImage(query.image.get());
-    if (io_surface_image) {
-      in_use = io_surface_image->CanCheckIOSurfaceIsInUse() &&
-               IOSurfaceIsInUse(io_surface_image->io_surface());
+    if (query.needs_gpu_memory_buffer_handle && io_surface_image) {
+      response.in_use_valid = io_surface_image->CanCheckIOSurfaceIsInUse();
+      response.gpu_memory_buffer_handle.type =
+          gfx::GpuMemoryBufferType::IO_SURFACE_BUFFER;
+      response.gpu_memory_buffer_handle.mach_port.reset(
+          IOSurfaceCreateMachPort(io_surface_image->io_surface()));
     }
-    response.in_use = in_use;
     params.in_use_responses.push_back(std::move(response));
   }
   ca_layer_in_use_queries_.clear();
 
   stub_->SendSwapBuffersCompleted(params);
 }
 
 gfx::SwapResult ImageTransportSurfaceOverlayMac::SwapBuffersInternal(
     const gfx::Rect& pixel_damage_rect) {
   TRACE_EVENT0("gpu", "ImageTransportSurfaceOverlayMac::SwapBuffersInternal");
@@ skipping 205 matching lines @@
   gl_renderer_id_ = context_renderer_id & kCGLRendererIDMatchingMask;
 
   // Post a task holding a reference to the new GL context. The reason for
   // this is to avoid creating-then-destroying the context for every image
   // transport surface that is observing the GPU switch.
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&IOSurfaceContextNoOp, context_on_new_gpu));
 }
 
 }  // namespace gpu