Move trial token code to content/common.

content/common/origin_trials/trial_token_validator.h

Index: content/common/origin_trials/trial_token_validator.h
diff --git a/content/common/origin_trials/trial_token_validator.h b/content/common/origin_trials/trial_token_validator.h
new file mode 100644
index 0000000000000000000000000000000000000000..d19c112169dcbfc1d32cb533a20682915d7752a5
--- /dev/null
+++ b/content/common/origin_trials/trial_token_validator.h
@@ -0,0 +1,26 @@
+// Copyright 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 CONTENT_COMMON_ORIGIN_TRIALS_TRIAL_TOKEN_VALIDATOR_H_
+#define CONTENT_COMMON_ORIGIN_TRIALS_TRIAL_TOKEN_VALIDATOR_H_
+
+#include <string>
+#include "base/strings/string_piece.h"
+#include "content/common/content_export.h"
+#include "url/origin.h"
+
+namespace content {
+
+namespace TrialTokenValidator {
+
+// This method is thread-safe.
+CONTENT_EXPORT bool ValidateToken(const std::string& token,
+                                  const url::Origin& origin,
+                                  base::StringPiece featureName);
+
+}  // namespace TrialTokenValidator
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_ORIGIN_TRIALS_TRIAL_TOKEN_VALIDATOR_H_