Ozone: Avoid blocking in Swapbuffer Call.

ui/gl/gl_surface.cc

Index: ui/gl/gl_surface.cc
diff --git a/ui/gl/gl_surface.cc b/ui/gl/gl_surface.cc
index e2f1717348538e6c01e42f6fb70cfff92ae2d4f4..19c0d2fbf43d8b49ce1962067f6d8e66da1db102 100644
--- a/ui/gl/gl_surface.cc
+++ b/ui/gl/gl_surface.cc
@@ -243,6 +243,10 @@ bool GLSurface::IsSurfaceless() const {
   return false;
 }
 
+void GLSurface::SetPageFlipCompletionCallback(
+    const PageFlipCompletionCallback& callback) {
+}
+
 GLSurface* GLSurface::GetCurrent() {
   return current_surface_.Pointer()->Get();
 }
@@ -364,6 +368,11 @@ bool GLSurfaceAdapter::IsSurfaceless() const {
   return surface_->IsSurfaceless();
 }
 
+void GLSurfaceAdapter::SetPageFlipCompletionCallback(
+    const PageFlipCompletionCallback& callback) {
+  surface_->SetPageFlipCompletionCallback(callback);
+}
+
 GLSurfaceAdapter::~GLSurfaceAdapter() {}
 
 }  // namespace gfx