ozone: Implement PlatformObject<T> for platform-specific objects

ui/ozone/ozone_platform.cc

 // Copyright 2013 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 "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "ui/ozone/ozone_platform.h"
-#include "ui/ozone/ozone_platform_list.h"
 #include "ui/ozone/ozone_switches.h"
+#include "ui/ozone/platform_object.h"
+#include "ui/ozone/platform_selection.h"
 
 namespace ui {
 
 namespace {
 
 bool g_platform_initialized_ui = false;
 bool g_platform_initialized_gpu = false;
 
-// Helper to construct an OzonePlatform by name using the platform list.
-OzonePlatform* CreatePlatform(const std::string& platform_name) {
-  // Search for a matching platform in the list.
-  for (int i = 0; i < kOzonePlatformCount; ++i)
-    if (platform_name == kOzonePlatforms[i].name)
-      return kOzonePlatforms[i].constructor();
-
-  LOG(FATAL) << "Invalid ozone platform: " << platform_name;
-  return NULL;  // not reached
 }
 
-// Returns the name of the platform to use (value of --ozone-platform flag).
-std::string GetPlatformName() {
-  // The first platform is the default.
-  if (!CommandLine::ForCurrentProcess()->HasSwitch(switches::kOzonePlatform) &&
-      kOzonePlatformCount > 0)
-    return kOzonePlatforms[0].name;
-  return CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
-      switches::kOzonePlatform);
-}
-
-}  // namespace
-
 OzonePlatform::OzonePlatform() {
   CHECK(!instance_) << "There should only be a single OzonePlatform.";
   instance_ = this;
   g_platform_initialized_ui = false;
   g_platform_initialized_gpu = false;
 }
 
 OzonePlatform::~OzonePlatform() {
   CHECK_EQ(instance_, this);
   instance_ = NULL;
@@ skipping 19 matching lines @@
 
 // static
 OzonePlatform* OzonePlatform::GetInstance() {
   CHECK(instance_) << "OzonePlatform is not initialized";
   return instance_;
 }
 
 // static
 void OzonePlatform::CreateInstance() {
   if (!instance_) {
-    std::string platform = GetPlatformName();
-    TRACE_EVENT1("ozone", "OzonePlatform::Initialize", "platform", platform);
-    CreatePlatform(platform);
+    TRACE_EVENT1("ozone",
+                 "OzonePlatform::Initialize",
+                 "platform",
+                 GetOzonePlatformName());
+    scoped_ptr<OzonePlatform> platform =
+        PlatformObject<OzonePlatform>::Create();
+
+    // TODO(spang): Currently need to leak this object.
+    CHECK_EQ(instance_, platform.release());
   }
 }
 
 // static
 OzonePlatform* OzonePlatform::instance_;
 
 }  // namespace ui