Refactor GL bindings so there is no global GLApi or DriverGL.

ui/gl/init/gl_factory_ozone.cc

Index: ui/gl/init/gl_factory_ozone.cc
diff --git a/ui/gl/init/gl_factory_ozone.cc b/ui/gl/init/gl_factory_ozone.cc
index f2d1cbd9aaaa996116060a63d067f4a5ee5fbf5c..aebda5deef0807581764c33177453fac05a6d77c 100644
--- a/ui/gl/init/gl_factory_ozone.cc
+++ b/ui/gl/init/gl_factory_ozone.cc
@@ -27,7 +27,8 @@ namespace init {
 namespace {
 
 bool HasDefaultImplementation(GLImplementation impl) {
-  return impl == kGLImplementationOSMesaGL || impl == kGLImplementationMockGL;
+  return impl == kGLImplementationOSMesaGL || impl == kGLImplementationMockGL ||
+         impl == kGLImplementationStubGL;
 }
 
 scoped_refptr<GLSurface> CreateDefaultViewGLSurface(
@@ -36,6 +37,7 @@ scoped_refptr<GLSurface> CreateDefaultViewGLSurface(
     case kGLImplementationOSMesaGL:
       return InitializeGLSurface(new GLSurfaceOSMesaHeadless());
     case kGLImplementationMockGL:
+    case kGLImplementationStubGL:
       return InitializeGLSurface(new GLSurfaceStub());
     default:
       NOTREACHED();
@@ -51,6 +53,7 @@ scoped_refptr<GLSurface> CreateDefaultOffscreenGLSurface(
           new GLSurfaceOSMesa(
               GLSurfaceFormat(GLSurfaceFormat::PIXEL_LAYOUT_BGRA), size));
     case kGLImplementationMockGL:
+    case kGLImplementationStubGL:
       return InitializeGLSurface(new GLSurfaceStub);
     default:
       NOTREACHED();
@@ -92,6 +95,12 @@ scoped_refptr<GLContext> CreateGLContext(GLShareGroup* share_group,
   switch (GetGLImplementation()) {
     case kGLImplementationMockGL:
       return scoped_refptr<GLContext>(new GLContextStub(share_group));
+    case kGLImplementationStubGL: {
+      scoped_refptr<GLContextStub> stub_context =
+          new GLContextStub(share_group);
+      stub_context->SetUseStubApi(true);
+      return stub_context;
+    }
     case kGLImplementationOSMesaGL:
       return InitializeGLContext(new GLContextOSMesa(share_group),
                                  compatible_surface, attribs);