Move code in ui/gl/* from gfx:: to gl::

ui/gl/gpu_switching_manager.h

Index: ui/gl/gpu_switching_manager.h
diff --git a/ui/gl/gpu_switching_manager.h b/ui/gl/gpu_switching_manager.h
index 913962b22c8992c9734e95e3ded5f33479d59865..4ac7620023518aed9b3693d759e59a838c1df7ce 100644
--- a/ui/gl/gpu_switching_manager.h
+++ b/ui/gl/gpu_switching_manager.h
@@ -33,7 +33,7 @@ class GL_EXPORT GpuSwitchingManager {
 
   // If no GPU is forced, return the original GpuPreference; otherwise, return
   // the forced GPU.
-  gfx::GpuPreference AdjustGpuPreference(gfx::GpuPreference gpu_preference);
+  gl::GpuPreference AdjustGpuPreference(gl::GpuPreference gpu_preference);
 
   // In the browser process, the value for this flag is computed the first time
   // this function is called.
@@ -65,7 +65,7 @@ class GL_EXPORT GpuSwitchingManager {
   void SwitchToDiscreteGpuMac();
 #endif  // OS_MACOSX
 
-  gfx::GpuPreference gpu_switching_option_;
+  gl::GpuPreference gpu_switching_option_;
   bool gpu_switching_option_set_;
 
   std::vector<uint32_t> vendor_ids_;