Refactor GL surface format handling

ui/gl/gl_surface_glx.h

Index: ui/gl/gl_surface_glx.h
diff --git a/ui/gl/gl_surface_glx.h b/ui/gl/gl_surface_glx.h
index 6d9842281e74eed432bbe95bd31b5e2e5ffdc39e..3d2838ba1d06fd168345b6e7c1e9b8ac432c03bd 100644
--- a/ui/gl/gl_surface_glx.h
+++ b/ui/gl/gl_surface_glx.h
@@ -61,7 +61,7 @@ class GL_EXPORT NativeViewGLSurfaceGLX : public GLSurfaceGLX {
   explicit NativeViewGLSurfaceGLX(gfx::AcceleratedWidget window);
 
   // Implement GLSurfaceGLX.
-  bool Initialize(GLSurface::Format format) override;
+  bool Initialize(GLSurfaceFormat format) override;
   void Destroy() override;
   bool Resize(const gfx::Size& size,
               float scale_factor,
@@ -120,7 +120,7 @@ class GL_EXPORT UnmappedNativeViewGLSurfaceGLX : public GLSurfaceGLX {
   explicit UnmappedNativeViewGLSurfaceGLX(const gfx::Size& size);
 
   // Implement GLSurfaceGLX.
-  bool Initialize(GLSurface::Format format) override;
+  bool Initialize(GLSurfaceFormat format) override;
   void Destroy() override;
   bool IsOffscreen() override;
   gfx::SwapResult SwapBuffers() override;