content: implement unittests backend for Ozone GBM

ui/ozone/public/ozone_gpu_test_helper.h

Index: ui/ozone/public/ozone_gpu_test_helper.h
diff --git a/ui/ozone/public/ozone_gpu_test_helper.h b/ui/ozone/public/ozone_gpu_test_helper.h
index e3428656ad5a680a93a9af67e98890e5298cced6..f4127cb27a2f3d7a4c2b6357d62489e54ef7c178 100644
--- a/ui/ozone/public/ozone_gpu_test_helper.h
+++ b/ui/ozone/public/ozone_gpu_test_helper.h
@@ -5,8 +5,10 @@
 #ifndef UI_OZONE_PUBLIC_OZONE_GPU_THREAD_HELPER_H_
 #define UI_OZONE_PUBLIC_OZONE_GPU_THREAD_HELPER_H_
 
+#include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/message_loop/message_loop.h"
 #include "ui/ozone/ozone_export.h"
 
 namespace base {
@@ -43,6 +45,22 @@ class OZONE_EXPORT OzoneGpuTestHelper {
   DISALLOW_COPY_AND_ASSIGN(OzoneGpuTestHelper);
 };
 
+// Helper class for tests to initialize both UI and GPU Ozone platform.
+class OZONE_EXPORT OzoneInitializerForTest {
+ public:
+  static scoped_ptr<OzoneInitializerForTest> Create();
+  ~OzoneInitializerForTest();
+
+ private:
+  OzoneInitializerForTest();
+  bool Initialize();
+
+  scoped_ptr<OzoneGpuTestHelper> gpu_helper_;
+  scoped_ptr<base::MessageLoop> message_loop_;
+
+  DISALLOW_COPY_AND_ASSIGN(OzoneInitializerForTest);
+};
+
 }  // namespace ui
 
 #endif  // UI_OZONE_PUBLIC_OZONE_GPU_THREAD_HELPER_H_