Move GPU blacklist and driver bug workaround list from json to data struct.

content/public/browser/gpu_data_manager.h

Index: content/public/browser/gpu_data_manager.h
diff --git a/content/public/browser/gpu_data_manager.h b/content/public/browser/gpu_data_manager.h
index a90aaa7ad3b782c5ba6021a0d9d280f49a12f6dd..ff6f1d9224983f8debea96e2cccd044e657c1114 100644
--- a/content/public/browser/gpu_data_manager.h
+++ b/content/public/browser/gpu_data_manager.h
@@ -31,8 +31,8 @@ class GpuDataManager {
   // Getter for the singleton.
   CONTENT_EXPORT static GpuDataManager* GetInstance();
 
-  virtual void InitializeForTesting(const std::string& gpu_blacklist_json,
-                                    const gpu::GPUInfo& gpu_info) = 0;
+  // This is only called by extensions testing.
+  virtual void BlacklistWebGLForTesting() = 0;
 
   virtual bool IsFeatureBlacklisted(int feature) const = 0;
   virtual bool IsFeatureEnabled(int feature) const = 0;