gpu: Add CHROMIUM_copy_image extension.

ui/gl/gl_surface_egl.h

Index: ui/gl/gl_surface_egl.h
diff --git a/ui/gl/gl_surface_egl.h b/ui/gl/gl_surface_egl.h
index 302c3eca00619039f0a73ca666baba5f127e2776..72f1252305f9b811ba9713947c881855478fd9b8 100644
--- a/ui/gl/gl_surface_egl.h
+++ b/ui/gl/gl_surface_egl.h
@@ -16,6 +16,8 @@
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
 #include "ui/gfx/geometry/size.h"
@@ -231,12 +233,23 @@ class GL_EXPORT SurfacelessEGL : public GLSurfaceEGL {
               bool has_alpha) override;
   EGLSurface GetHandle() override;
   void* GetShareHandle() override;
+  bool SupportsInsertFence() override;
+  void InsertFence(const base::Closure& callback) override;
 
  protected:
   ~SurfacelessEGL() override;
 
+  bool InsertSyncFence(const EGLint* attribs, const base::Closure& callback);
+
  private:
+  class EGLWaitSyncFenceThread;
+
+  void FenceRetired(EGLSyncKHR fence, const base::Closure& callback);
+
   gfx::Size size_;
+  scoped_refptr<EGLWaitSyncFenceThread> wait_sync_fence_thread_;
+  base::WeakPtrFactory<SurfacelessEGL> weak_ptr_factory_;
+
   DISALLOW_COPY_AND_ASSIGN(SurfacelessEGL);
 };