ozone: Initialize a subsystem only if necessary.

ui/ozone/ozone_platform.h

Index: ui/ozone/ozone_platform.h
diff --git a/ui/ozone/ozone_platform.h b/ui/ozone/ozone_platform.h
index 536ff0ed8e26e1182acde7e698293f7533f0e663..48d29eb5e65d27f5eb84e28e55219401b2e602b8 100644
--- a/ui/ozone/ozone_platform.h
+++ b/ui/ozone/ozone_platform.h
@@ -38,9 +38,12 @@ class OZONE_EXPORT OzonePlatform {
   OzonePlatform();
   virtual ~OzonePlatform();
 
-  // Initialize the platform. Once complete, SurfaceFactoryOzone &
-  // EventFactoryOzone will be set.
-  static void Initialize();
+  // Initializes the subsystems/resources necessary for the UI process (e.g.
+  // events, surface, etc.)
+  static void InitializeForUI();
+
+  // Initializes the subsystems/resources necessary for the GPU process.
+  static void InitializeForGPU();
 
   static OzonePlatform* GetInstance();