Revert of Get rid of gpu related switches by passing gpu::GpuPreferences via IPC.

content/gpu/gpu_child_thread.h

Index: content/gpu/gpu_child_thread.h
diff --git a/content/gpu/gpu_child_thread.h b/content/gpu/gpu_child_thread.h
index 80a24127f02b3d571b2e84a9272658c18d36b1b9..ec7d19edc993e7a7d1c98e9b94affa5c3c2860ad 100644
--- a/content/gpu/gpu_child_thread.h
+++ b/content/gpu/gpu_child_thread.h
@@ -71,6 +71,8 @@
   void Init(const base::Time& process_start_time);
   void StopWatchdog();
 
+  static gpu::GpuPreferences GetGpuPreferencesFromCommandLine();
+
  private:
   // ChildThread overrides.
   bool Send(IPC::Message* msg) override;
@@ -101,7 +103,7 @@
                          const std::string& shader) override;
 
   // Message handlers.
-  void OnInitialize(const gpu::GpuPreferences& gpu_preferences);
+  void OnInitialize();
   void OnFinalize();
   void OnCollectGraphicsInfo();
   void OnGetVideoMemoryUsageStats();