Add OzoneGLImpl interface.

ui/gl/init/gl_initializer_ozone.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/gl/init/gl_initializer.h"
 
 #include "base/logging.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_egl_api_implementation.h"
 #include "ui/gl/gl_gl_api_implementation.h"
 #include "ui/gl/gl_implementation_osmesa.h"
 #include "ui/gl/gl_osmesa_api_implementation.h"
 #include "ui/gl/gl_surface_egl.h"
+#include "ui/gl/init/ozone_util.h"
 #include "ui/ozone/public/ozone_platform.h"
 #include "ui/ozone/public/surface_factory_ozone.h"
 
 namespace gl {
 namespace init {
 
 namespace {
 
-ui::SurfaceFactoryOzone* GetSurfaceFactory() {
-  return ui::OzonePlatform::GetInstance()->GetSurfaceFactoryOzone();
-}
-
 bool InitializeStaticEGLInternal() {
   if (!GetSurfaceFactory()->LoadEGLGLES2Bindings())
     return false;
 
   SetGLImplementation(kGLImplementationEGLGLES2);
   InitializeStaticGLBindingsGL();
   InitializeStaticGLBindingsEGL();
 
   return true;
 }
 
 }  // namespace
 
 bool InitializeGLOneOffPlatform() {
+  if (HasGLOzone())
+    return GetGLOzone()->InitializeGLOneOffPlatform();
+
   switch (GetGLImplementation()) {
     case kGLImplementationEGLGLES2:
       if (!GLSurfaceEGL::InitializeOneOff(
               GetSurfaceFactory()->GetNativeDisplay())) {
         LOG(ERROR) << "GLSurfaceEGL::InitializeOneOff failed.";
         return false;
       }
       return true;
     case kGLImplementationOSMesaGL:
     case kGLImplementationMockGL:
       return true;
     default:
       return false;
   }
 }
 
 bool InitializeStaticGLBindings(GLImplementation implementation) {
   // Prevent reinitialization with a different implementation. Once the gpu
   // unit tests have initialized with kGLImplementationMock, we don't want to
   // later switch to another GL implementation.
   DCHECK_EQ(kGLImplementationNone, GetGLImplementation());
-  ui::OzonePlatform::InitializeForGPU();

[piman, 2016/08/31 20:05:09]

nit: because this moves to >1 location, is there a way to add a DCHECK somewhere
to make sure we didn't miss any?

[kylechar, 2016/09/01 13:57:21]

I can add an explicit DCHECK(OzonePlatform::GetInstance()) at the start of
InitializeGLOneOffPlatform() and InitializeStaticGLBindings() for sure.

Realistically it doesn't make much difference because
OzonePlatform::GetInstance() has it's own DCHECK, so that will be what fails. It
would also be what fails now on the first HasGLOzone() call in both of those
methods.

Another option is to move OzonePlatform::InitializeForGPU() to gpu_main.cc. It's
conceptually much nicer for Chrome because initializing OzonePlatform as part of
GL initialization seems flawed. What if we don't want to initialize GL (eg.
Vulkan) then OzonePlatform doesn't get initialized. The big problem with this is
there are ~10 unit tests that also need to initialize OzonePlatform in their
main or test fixture.

[piman, 2016/09/01 17:43:04]

Ok, if it's redundant, then nbd.
It may make sense to have it both in gpu_main.cc and GLSurfaceTestSupport,
because the latter is intended to initialize all the platform requirements for
GPU, indeed to avoid having to maintain 10ish test suites. Up to you.

+
+  if (HasGLOzone(implementation)) {
+    return GetGLOzone(implementation)
+        ->InitializeStaticGLBindings(implementation);
+  }
 
   switch (implementation) {
     case kGLImplementationOSMesaGL:
       return InitializeStaticGLBindingsOSMesaGL();
     case kGLImplementationEGLGLES2:
       return InitializeStaticEGLInternal();
     case kGLImplementationMockGL:
       SetGLImplementation(kGLImplementationMockGL);
       InitializeStaticGLBindingsGL();
       return true;
     default:
       NOTREACHED();
   }
 
   return false;
 }
 
 void InitializeDebugGLBindings() {
+  if (HasGLOzone()) {
+    GetGLOzone()->InitializeDebugGLBindings();
+    return;
+  }
+
   InitializeDebugGLBindingsEGL();
   InitializeDebugGLBindingsGL();
   InitializeDebugGLBindingsOSMESA();
 }
 
 void ClearGLBindingsPlatform() {
+  if (HasGLOzone()) {
+    GetGLOzone()->ClearGLBindings();
+    return;
+  }
+
   ClearGLBindingsEGL();
   ClearGLBindingsGL();
   ClearGLBindingsOSMESA();
 }
 
 }  // namespace init
 }  // namespace gl