Revert 205481 "Virtual context MakeCurrent tweaks."

trunk/src/content/common/gpu/image_transport_surface_mac.cc

Index: trunk/src/content/common/gpu/image_transport_surface_mac.cc
===================================================================
--- trunk/src/content/common/gpu/image_transport_surface_mac.cc	(revision 205969)
+++ trunk/src/content/common/gpu/image_transport_surface_mac.cc	(working copy)
@@ -6,7 +6,6 @@
 
 #include "base/mac/scoped_cftyperef.h"
 #include "base/memory/scoped_ptr.h"
-#include "content/common/gpu/gpu_command_buffer_stub.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gl/gl_bindings.h"
@@ -34,10 +33,8 @@
 
 // We are backed by an offscreen surface for the purposes of creating
 // a context, but use FBOs to render to texture backed IOSurface
-class IOSurfaceImageTransportSurface
-    : public gfx::NoOpGLSurfaceCGL,
-      public ImageTransportSurface,
-      public GpuCommandBufferStub::DestructionObserver {
+class IOSurfaceImageTransportSurface : public gfx::NoOpGLSurfaceCGL,
+                                       public ImageTransportSurface {
  public:
   IOSurfaceImageTransportSurface(GpuChannelManager* manager,
                                  GpuCommandBufferStub* stub,
@@ -65,9 +62,6 @@
   virtual void OnResize(gfx::Size size, float scale_factor) OVERRIDE;
   virtual void SetLatencyInfo(const ui::LatencyInfo&) OVERRIDE;
 
-  // GpuCommandBufferStub::DestructionObserver implementation.
-  virtual void OnWillDestroyStub() OVERRIDE;
-
  private:
   virtual ~IOSurfaceImageTransportSurface() OVERRIDE;
 
@@ -144,6 +138,7 @@
 }
 
 IOSurfaceImageTransportSurface::~IOSurfaceImageTransportSurface() {
+  Destroy();
 }
 
 bool IOSurfaceImageTransportSurface::Initialize() {
@@ -156,14 +151,7 @@
 
   if (!helper_->Initialize())
     return false;
-
-  if (!NoOpGLSurfaceCGL::Initialize()) {
-    helper_->Destroy();
-    return false;
-  }
-
-  helper_->stub()->AddDestructionObserver(this);
-  return true;
+  return NoOpGLSurfaceCGL::Initialize();
 }
 
 void IOSurfaceImageTransportSurface::Destroy() {
@@ -325,11 +313,6 @@
   latency_info_ = latency_info;
 }
 
-void IOSurfaceImageTransportSurface::OnWillDestroyStub() {
-  helper_->stub()->RemoveDestructionObserver(this);
-  Destroy();
-}
-
 void IOSurfaceImageTransportSurface::UnrefIOSurface() {
   // If we have resources to destroy, then make sure that we have a current
   // context which we can use to delete the resources.