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

components/display_compositor/yuv_readback_unittest.cc

Index: components/display_compositor/yuv_readback_unittest.cc
diff --git a/components/display_compositor/yuv_readback_unittest.cc b/components/display_compositor/yuv_readback_unittest.cc
index 75d2dd648d39ddfa129a8b97f72ad1e70ffdc96b..b336137bbdbda77e1e2df5b118ddfb04a27af24c 100644
--- a/components/display_compositor/yuv_readback_unittest.cc
+++ b/components/display_compositor/yuv_readback_unittest.cc
@@ -45,7 +45,7 @@ class YUVReadbackTest : public testing::Test {
         gfx::kNullAcceleratedWidget, /* window */
         gfx::Size(1, 1),             /* size */
         nullptr,                     /* share_context */
-        attributes, gfx::PreferDiscreteGpu, gpu::SharedMemoryLimits(),
+        attributes, gl::PreferDiscreteGpu, gpu::SharedMemoryLimits(),
         nullptr, /* gpu_memory_buffer_manager */
         nullptr /* image_factory */));
     gl_ = context_->GetImplementation();
@@ -472,7 +472,7 @@ class YUVReadbackTest : public testing::Test {
   std::unique_ptr<gpu::GLInProcessContext> context_;
   gpu::gles2::GLES2Interface* gl_;
   std::unique_ptr<display_compositor::GLHelper> helper_;
-  gfx::DisableNullDrawGLBindings enable_pixel_output_;
+  gl::DisableNullDrawGLBindings enable_pixel_output_;
   base::MessageLoop message_loop_;
 };