Move content settings extension API to content_settings dir.

chrome/browser/extensions/extension_content_settings_helpers.h

-// Copyright (c) 2011 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_BROWSER_EXTENSIONS_EXTENSION_CONTENT_SETTINGS_HELPERS_H__
-#define CHROME_BROWSER_EXTENSIONS_EXTENSION_CONTENT_SETTINGS_HELPERS_H__
-#pragma once
-
-#include <string>
-
-#include "chrome/common/content_settings.h"
-#include "chrome/common/content_settings_pattern.h"
-
-namespace extension_content_settings_helpers {
-
-// Parses an extension match pattern and returns a corresponding
-// content settings pattern object.
-// If |pattern_str| is invalid or can't be converted to a content settings
-// pattern, |error| is set to the parsing error and an invalid pattern
-// is returned.
-ContentSettingsPattern ParseExtensionPattern(const std::string& pattern_str,
-                                             std::string* error);
-
-// Converts a content settings type string to the corresponding
-// ContentSettingsType. Returns CONTENT_SETTINGS_TYPE_DEFAULT if the string
-// didn't specify a valid content settings type.
-ContentSettingsType StringToContentSettingsType(
-    const std::string& content_type);
-// Returns a string representation of a ContentSettingsType.
-const char* ContentSettingsTypeToString(ContentSettingsType type);
-
-// Converts a content setting string to the corresponding ContentSetting.
-// Returns true if |setting_str| specifies a valid content setting,
-// false otherwise.
-bool StringToContentSetting(const std::string& setting_str,
-                            ContentSetting* setting);
-// Returns a string representation of a ContentSetting.
-const char* ContentSettingToString(ContentSetting setting);
-
-}  // namespace extension_content_settings_helpers
-
-#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_CONTENT_SETTINGS_HELPERS_H__