Revert of cc: Implement shared worker contexts. (patchset #9 id:160001 of https://codereview.chromium.org/1336733002/ )

Reason for revert:
Broke GPU rasterization on Mac OS; please see https://code.google.com/p/chromium/issues/detail?id=523411#c26 .

I'm really sorry -- I don't know how this got past the CQ.

Original issue's description:
> cc: Implement shared worker contexts.
>
> This moves the responsibility to call BindToCurrentThread/SetupLock out
> of cc::OutputSurface and to the maintainer of the (possibly) shared
> context.
>
> OutputSurface now needs to be destroyed on the same thread they
> were created. OutputSurface::DetachFromClient() can be used to
> destroy any resources that need to be destroyed on the thread
> that the OutputSurface has been bound to.
>
> BUG=523411
> CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
>
> Committed: https://crrev.com/a47ef41ea03d3a5b8965eb700b682ddf8a1f055a
> Cr-Commit-Position: refs/heads/master@{#349274}

TBR=danakj@chromium.org,piman@chromium.org,sievers@chromium.org,reveman@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=523411

Review URL: https://codereview.chromium.org/1356463002

Cr-Commit-Position: refs/heads/master@{#349313}

4 files changed, 8 insertions, 49 deletions

diff --git a/content/browser/android/in_process/synchronous_compositor_factory_impl.cc b/content/browser/android/in_process/synchronous_compositor_factory_impl.cc
index 9888c2d..b90edd6 100644
--- a/content/browser/android/in_process/synchronous_compositor_factory_impl.cc
+++ b/content/browser/android/in_process/synchronous_compositor_factory_impl.cc
@@ -24,7 +24,6 @@
 #include "content/renderer/render_thread_impl.h"
 #include "gpu/blink/webgraphicscontext3d_in_process_command_buffer_impl.h"
 #include "gpu/command_buffer/client/gl_in_process_context.h"
-#include "gpu/command_buffer/client/gles2_interface.h"
 #include "gpu/command_buffer/common/gles2_cmd_utils.h"
 #include "ui/gl/android/surface_texture.h"
 #include "ui/gl/gl_surface.h"
@@ -170,40 +169,11 @@ SynchronousCompositorFactoryImpl::CreateOutputSurface(
     scoped_refptr<content::FrameSwapMessageQueue> frame_swap_message_queue) {
   scoped_refptr<cc::ContextProvider> onscreen_context =
       CreateContextProviderForCompositor(surface_id, RENDER_COMPOSITOR_CONTEXT);
-
-  bool shared_worker_context_lost = false;
-  if (shared_worker_context_) {
-    // Note: If context is lost, we delete reference after releasing the lock.
-    base::AutoLock lock(*shared_worker_context_->GetLock());
-    if (shared_worker_context_->ContextGL()->GetGraphicsResetStatusKHR() !=
-        GL_NO_ERROR) {
-      shared_worker_context_lost = true;
-    }
-  }
-  // Note: shared worker context support requires |use_ipc_command_buffer_|.
-  if (use_ipc_command_buffer_ &&
-      (!shared_worker_context_ || shared_worker_context_lost)) {
-    // TODO(reveman): This limit is based on the usage required by async
-    // uploads. Determine what a good limit is now that async uploads are
-    // no longer used.
-    unsigned int mapped_memory_reclaim_limit =
-        (base::SysInfo::IsLowEndDevice() ? 2 : 6) * 1024 * 1024;
-    WebGraphicsContext3DCommandBufferImpl::SharedMemoryLimits mem_limits;
-    mem_limits.mapped_memory_reclaim_limit = mapped_memory_reclaim_limit;
-    scoped_ptr<WebGraphicsContext3DCommandBufferImpl> context =
-        CreateContext3D(0, GetDefaultAttribs(), mem_limits);
-    shared_worker_context_ =
-        make_scoped_refptr(new SynchronousCompositorContextProvider(
-            context.Pass(), RENDER_WORKER_CONTEXT));
-    if (!shared_worker_context_->BindToCurrentThread())
-      shared_worker_context_ = nullptr;
-    if (shared_worker_context_)
-      shared_worker_context_->SetupLock();
-  }
+  scoped_refptr<cc::ContextProvider> worker_context =
+      CreateContextProviderForCompositor(0, RENDER_WORKER_CONTEXT);
 
   return make_scoped_ptr(new SynchronousCompositorOutputSurface(
-      onscreen_context, shared_worker_context_, routing_id,
-      frame_swap_message_queue));
+      onscreen_context, worker_context, routing_id, frame_swap_message_queue));
 }
 
 InputHandlerManagerClient*
@@ -241,9 +211,6 @@ SynchronousCompositorFactoryImpl::CreateContextProviderForCompositor(
   // This is half of what RenderWidget uses because synchronous compositor
   // pipeline is only one frame deep. But twice of half for low end here
   // because 16bit texture is not supported.
-  // TODO(reveman): This limit is based on the usage required by async
-  // uploads. Determine what a good limit is now that async uploads are
-  // no longer used.
   unsigned int mapped_memory_reclaim_limit =
       (base::SysInfo::IsLowEndDevice() ? 2 : 6) * 1024 * 1024;
   blink::WebGraphicsContext3D::Attributes attributes = GetDefaultAttribs();
diff --git a/content/browser/android/in_process/synchronous_compositor_factory_impl.h b/content/browser/android/in_process/synchronous_compositor_factory_impl.h
index 342b2a9..84ceb03 100644
--- a/content/browser/android/in_process/synchronous_compositor_factory_impl.h
+++ b/content/browser/android/in_process/synchronous_compositor_factory_impl.h
@@ -28,7 +28,6 @@ class WebGraphicsContext3DInProcessCommandBufferImpl;
 namespace content {
 
 class InProcessChildThreadParams;
-class SynchronousCompositorContextProvider;
 
 class SynchronousCompositorFactoryImpl : public SynchronousCompositorFactory {
  public:
@@ -89,8 +88,6 @@ class SynchronousCompositorFactoryImpl : public SynchronousCompositorFactory {
   class VideoContextProvider;
   scoped_refptr<VideoContextProvider> video_context_provider_;
 
-  scoped_refptr<SynchronousCompositorContextProvider> shared_worker_context_;
-
   bool use_ipc_command_buffer_;
 
   // |num_hardware_compositor_lock_| is updated on UI thread only but can be
diff --git a/content/browser/android/in_process/synchronous_compositor_output_surface.cc b/content/browser/android/in_process/synchronous_compositor_output_surface.cc
index f03f992..85c7bcb 100644
--- a/content/browser/android/in_process/synchronous_compositor_output_surface.cc
+++ b/content/browser/android/in_process/synchronous_compositor_output_surface.cc
@@ -83,6 +83,11 @@ SynchronousCompositorOutputSurface::SynchronousCompositorOutputSurface(
 }
 
 SynchronousCompositorOutputSurface::~SynchronousCompositorOutputSurface() {
+  DCHECK(CalledOnValidThread());
+  if (registered_) {
+    SynchronousCompositorRegistry::GetInstance()->UnregisterOutputSurface(
+        routing_id_, this);
+  }
 }
 
 bool SynchronousCompositorOutputSurface::BindToClient(
@@ -100,15 +105,6 @@ bool SynchronousCompositorOutputSurface::BindToClient(
   return true;
 }
 
-void SynchronousCompositorOutputSurface::DetachFromClient() {
-  DCHECK(CalledOnValidThread());
-  if (registered_) {
-    SynchronousCompositorRegistry::GetInstance()->UnregisterOutputSurface(
-        routing_id_, this);
-  }
-  cc::OutputSurface::DetachFromClient();
-}
-
 void SynchronousCompositorOutputSurface::SetCompositor(
     SynchronousCompositorImpl* compositor) {
   DCHECK(CalledOnValidThread());
diff --git a/content/browser/android/in_process/synchronous_compositor_output_surface.h b/content/browser/android/in_process/synchronous_compositor_output_surface.h
index b1baa64..4146952 100644
--- a/content/browser/android/in_process/synchronous_compositor_output_surface.h
+++ b/content/browser/android/in_process/synchronous_compositor_output_surface.h
@@ -58,7 +58,6 @@ class SynchronousCompositorOutputSurface
 
   // OutputSurface.
   bool BindToClient(cc::OutputSurfaceClient* surface_client) override;
-  void DetachFromClient() override;
   void Reshape(const gfx::Size& size, float scale_factor) override;
   void SwapBuffers(cc::CompositorFrame* frame) override;
   void Invalidate() override;