Allow command-line arguments to override EF public key

chrome/renderer/origin_trials/origin_trial_key_manager.h

 // Copyright (c) 2016 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.
 
 #ifndef CHROME_RENDERER_ORIGIN_TRIALS_ORIGIN_TRIAL_KEY_MANAGER_H_
 #define CHROME_RENDERER_ORIGIN_TRIALS_ORIGIN_TRIAL_KEY_MANAGER_H_
 
+#include <string>
+
+#include "base/macros.h"
 #include "base/strings/string_piece.h"
 
 class OriginTrialKeyManager {
  public:
-  base::StringPiece GetPublicKey();
+  OriginTrialKeyManager();
+  ~OriginTrialKeyManager();
+
+  bool SetPublicKeyFromASCIIString(const std::string& ascii_public_key);
+  base::StringPiece GetPublicKey() const;
+
+ private:
+  std::string public_key_;
+
+  DISALLOW_COPY_AND_ASSIGN(OriginTrialKeyManager);
 };
 
 #endif  // CHROME_RENDERER_ORIGIN_TRIALS_ORIGIN_TRIAL_KEY_MANAGER_H_