Move trial token code to content/common.

chrome/renderer/origin_trials/origin_trial_key_manager.cc

-// 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.
-
-#include "chrome/renderer/origin_trials/origin_trial_key_manager.h"
-
-#include <stdint.h>
-
-// This is the default public key used for validating signatures.
-// TODO(iclelland): Provide a mechanism to allow for multiple signing keys.
-// https://crbug.com/584737
-// TODO(iclelland): Provide a mechanism to override, replace or disable this key
-// with field trials.
-static const uint8_t kPublicKey[] = {
-    0x7c, 0xc4, 0xb8, 0x9a, 0x93, 0xba, 0x6e, 0xe2, 0xd0, 0xfd, 0x03,
-    0x1d, 0xfb, 0x32, 0x66, 0xc7, 0x3b, 0x72, 0xfd, 0x54, 0x3a, 0x07,
-    0x51, 0x14, 0x66, 0xaa, 0x02, 0x53, 0x4e, 0x33, 0xa1, 0x15,
-};
-
-base::StringPiece OriginTrialKeyManager::GetPublicKey() {
-  return base::StringPiece(reinterpret_cast<const char*>(kPublicKey),
-                           arraysize(kPublicKey));
-}