Set autoplay gesture override experiment based on finch trial group.

content/public/common/web_preferences.h

 // Copyright 2014 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_PUBLIC_COMMON_WEB_PREFERENCES_H_
 #define CONTENT_PUBLIC_COMMON_WEB_PREFERENCES_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 43 matching lines @@
 
 // The ISO 15924 script code for undetermined script aka Common. It's the
 // default used on WebKit's side to get/set a font setting when no script is
 // specified.
 CONTENT_EXPORT extern const char kCommonScript[];
 
 // A struct for managing blink's settings.
 //
 // Adding new values to this class probably involves updating
 // blink::WebSettings, content/common/view_messages.h, browser/tab_contents/
-// render_view_host_delegate_helper.cc, and browser/profiles/profile.cc.
+// render_view_host_delegate_helper.cc, browser/profiles/profile.cc,
+// and content/public/common/common_param_traits_macros.h
 struct CONTENT_EXPORT WebPreferences {
   ScriptFontFamilyMap standard_font_family_map;
   ScriptFontFamilyMap fixed_font_family_map;
   ScriptFontFamilyMap serif_font_family_map;
   ScriptFontFamilyMap sans_serif_font_family_map;
   ScriptFontFamilyMap cursive_font_family_map;
   ScriptFontFamilyMap fantasy_font_family_map;
   ScriptFontFamilyMap pictograph_font_family_map;
   int default_font_size;
   int default_fixed_font_size;
@@ skipping 129 matching lines @@
   bool use_wide_viewport;
   bool force_zero_layout_height;
   bool viewport_meta_layout_size_quirk;
   bool viewport_meta_merge_content_quirk;
   bool viewport_meta_non_user_scalable_quirk;
   bool viewport_meta_zero_values_quirk;
   bool clobber_user_agent_initial_scale_quirk;
   bool ignore_main_frame_overflow_hidden_quirk;
   bool report_screen_size_in_physical_pixels_quirk;
   bool record_whole_document;
+  std::string autoplay_experiment_mode;
 #endif
 
   // Default (used if the page or UA doesn't override these) values for page
   // scale limits. These are set directly on the WebView so there's no analogue
   // in WebSettings.
   float default_minimum_page_scale_factor;
   float default_maximum_page_scale_factor;
 
   // We try to keep the default values the same as the default values in
   // chrome, except for the cases where it would require lots of extra work for
   // the embedder to use the same default value.
   WebPreferences();
   ~WebPreferences();
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_COMMON_WEB_PREFERENCES_H_