gpu: Don't call SetSwapInterval() for NullTransportSurface

BUG=419876

Review URL: https://codereview.chromium.org/649773002

Cr-Commit-Position: refs/heads/master@{#299199}

content/common/gpu/null_transport_surface.cc

@@ -64,4 +64,10 @@ void NullTransportSurface::SendVSyncUpdateIfAvailable() {
   NOTREACHED();
 }
 
+bool NullTransportSurface::OnMakeCurrent(gfx::GLContext* context) {
+  // Override PassThroughImageTransportSurface default behavior which
+  // sets the swap interval.
+  return true;
+}
+
 }  // namespace content

content/common/gpu/null_transport_surface.h

@@ -20,11 +20,12 @@ class NullTransportSurface : public PassThroughImageTransportSurface {
                        GpuCommandBufferStub* stub,
                        const gfx::GLSurfaceHandle& handle);
 
-  // gfx::GLSurface implementation.
+  // gfx::GLSurfaceAdapter implementation.
   virtual bool Initialize() override;
   virtual void Destroy() override;
   virtual bool SwapBuffers() override;
   virtual bool PostSubBuffer(int x, int y, int width, int height) override;
+  virtual bool OnMakeCurrent(gfx::GLContext* context) override;
 
  protected:
   virtual ~NullTransportSurface();