Add 'autoplay' content settings and expose it to Blink.

components/content_settings/core/common/content_settings.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 COMPONENTS_CONTENT_SETTINGS_CORE_COMMON_CONTENT_SETTINGS_H_
 #define COMPONENTS_CONTENT_SETTINGS_CORE_COMMON_CONTENT_SETTINGS_H_
 
 #include <stddef.h>
 
 #include <string>
@@ skipping 41 matching lines @@
   bool incognito;
 };
 
 typedef std::vector<ContentSettingPatternSource> ContentSettingsForOneType;
 
 struct RendererContentSettingRules {
   RendererContentSettingRules();
   ~RendererContentSettingRules();
   ContentSettingsForOneType image_rules;
   ContentSettingsForOneType script_rules;
+  ContentSettingsForOneType autoplay_rules;
 };
 
 namespace content_settings {
 
 typedef std::string ResourceIdentifier;
 
 // Enum containing the various source for content settings. Settings can be
 // set by policy, extension, the user or by the custodian of a supervised user.
 // Certain (internal) schemes are whilelisted. For whilelisted schemes the
 // source is |SETTING_SOURCE_WHITELIST|.
@@ skipping 11 matching lines @@
 // contains the patterns of the appling rule.
 struct SettingInfo {
   SettingSource source;
   ContentSettingsPattern primary_pattern;
   ContentSettingsPattern secondary_pattern;
 };
 
 }  // namespace content_settings
 
 #endif  // COMPONENTS_CONTENT_SETTINGS_CORE_COMMON_CONTENT_SETTINGS_H_