Add disabled origin trial feature list

content/public/common/content_client.h

Index: content/public/common/content_client.h
diff --git a/content/public/common/content_client.h b/content/public/common/content_client.h
index f0862d5b40ac4d16b6bc2b3aa3d8b60f499455d2..dc2c54feea007070a35df8800be0c242735158cf 100644
--- a/content/public/common/content_client.h
+++ b/content/public/common/content_client.h
@@ -172,6 +172,10 @@ class CONTENT_EXPORT ContentClient {
   // origin trials are not enabled in this context.
   virtual base::StringPiece GetOriginTrialPublicKey();
 
+  // Returns true if the named experimental feature should be disabled in origin
+  // trials, even if a valid token is present.
+  virtual bool IsOriginTrialFeatureDisabled(base::StringPiece feature);
+
 #if defined(OS_ANDROID)
   // Returns true for clients like Android WebView that uses synchronous
   // compositor. Note setting this to true will permit synchronous IPCs from