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

cc/output/output_surface.cc

Index: cc/output/output_surface.cc
diff --git a/cc/output/output_surface.cc b/cc/output/output_surface.cc
index dd100f4c0df903d6ccaf1ab05606ed89c97f3d0b..9ee9807ecdb90bf2ecdf2afb78b99ea6f3a7ee77 100644
--- a/cc/output/output_surface.cc
+++ b/cc/output/output_surface.cc
@@ -69,12 +69,12 @@ class SkiaGpuTraceMemoryDump : public SkTraceMemoryDump {
     base::trace_event::MemoryAllocatorDumpGuid guid;
 
     if (strcmp(backing_type, kGLTextureBackingType) == 0) {
-      guid = gfx::GetGLTextureClientGUIDForTracing(share_group_tracing_guid_,
-                                                   gl_id);
+      guid = gl::GetGLTextureClientGUIDForTracing(share_group_tracing_guid_,
+                                                  gl_id);
     } else if (strcmp(backing_type, kGLBufferBackingType) == 0) {
-      guid = gfx::GetGLBufferGUIDForTracing(tracing_process_id, gl_id);
+      guid = gl::GetGLBufferGUIDForTracing(tracing_process_id, gl_id);
     } else if (strcmp(backing_type, kGLRenderbufferBackingType) == 0) {
-      guid = gfx::GetGLRenderbufferGUIDForTracing(tracing_process_id, gl_id);
+      guid = gl::GetGLRenderbufferGUIDForTracing(tracing_process_id, gl_id);
     }
 
     if (!guid.empty()) {