Refactor GL surface format handling

ui/gl/gl_surface_glx.cc

Index: ui/gl/gl_surface_glx.cc
diff --git a/ui/gl/gl_surface_glx.cc b/ui/gl/gl_surface_glx.cc
index 2ba52fbf61cad8e78e78df3f2213dc68ab2096a2..37ef1103c1fdde836dde4b14c509e3d1b3e1d4fe 100644
--- a/ui/gl/gl_surface_glx.cc
+++ b/ui/gl/gl_surface_glx.cc
@@ -513,7 +513,7 @@ GLXDrawable NativeViewGLSurfaceGLX::GetDrawableHandle() const {
   return glx_window_;
 }
 
-bool NativeViewGLSurfaceGLX::Initialize(GLSurface::Format format) {
+bool NativeViewGLSurfaceGLX::Initialize(GLSurfaceFormat format) {
   XWindowAttributes attributes;
   if (!XGetWindowAttributes(g_display, parent_window_, &attributes)) {
     LOG(ERROR) << "XGetWindowAttributes failed for window " << parent_window_
@@ -657,7 +657,7 @@ UnmappedNativeViewGLSurfaceGLX::UnmappedNativeViewGLSurfaceGLX(
     size_.SetSize(1, 1);
 }
 
-bool UnmappedNativeViewGLSurfaceGLX::Initialize(GLSurface::Format format) {
+bool UnmappedNativeViewGLSurfaceGLX::Initialize(GLSurfaceFormat format) {
   DCHECK(!window_);
 
   gfx::AcceleratedWidget parent_window = DefaultRootWindow(g_display);