Add CSS variables feature flag to chrome://flags.

webkit/glue/webpreferences.cc

 // Copyright (c) 2012 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 "webkit/glue/webpreferences.h"
 
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebNetworkStateNotifier.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebRuntimeFeatures.h"
@@ skipping 84 matching lines @@
       memory_info_enabled(false),
       fullscreen_enabled(false),
       allow_displaying_insecure_content(true),
       allow_running_insecure_content(false),
       password_echo_enabled(false),
       should_print_backgrounds(false),
       enable_scroll_animator(false),
       visual_word_movement_enabled(false),
       css_regions_enabled(false),
       css_shaders_enabled(false),
+      css_variables_enabled(false),
       device_supports_touch(false),
       device_supports_mouse(true),
 #if !defined(WEBCOMPOSITOR_OWNS_SETTINGS)
       threaded_animation_enabled(false),
       per_tile_painting_enabled(false),
       partial_swap_enabled(false),
 #endif
       default_tile_width(256),
       default_tile_height(256),
       max_untiled_layer_width(512),
@@ skipping 265 matching lines @@
   settings->setFullScreenEnabled(fullscreen_enabled);
   settings->setAllowDisplayOfInsecureContent(allow_displaying_insecure_content);
   settings->setAllowRunningOfInsecureContent(allow_running_insecure_content);
   settings->setPasswordEchoEnabled(password_echo_enabled);
   settings->setShouldPrintBackgrounds(should_print_backgrounds);
   settings->setEnableScrollAnimator(enable_scroll_animator);
   settings->setVisualWordMovementEnabled(visual_word_movement_enabled);
 
   settings->setExperimentalCSSRegionsEnabled(css_regions_enabled);
   settings->setExperimentalCSSCustomFilterEnabled(css_shaders_enabled);
+  settings->setExperimentalCSSVariablesEnabled(css_variables_enabled);
 
   settings->setDeviceSupportsTouch(device_supports_touch);
   settings->setDeviceSupportsMouse(device_supports_mouse);
 
 #if !defined(WEBCOMPOSITOR_OWNS_SETTINGS)
   settings->setThreadedAnimationEnabled(threaded_animation_enabled);
 
   // Enable per-tile painting if requested on the command line.
   settings->setPerTilePaintingEnabled(per_tile_painting_enabled);
 
   // Enable partial swaps if specified form the command line.
   settings->setPartialSwapEnabled(partial_swap_enabled);
 #endif
 
   settings->setDefaultTileSize(
       WebSize(default_tile_width, default_tile_height));
   settings->setMaxUntiledLayerSize(
       WebSize(max_untiled_layer_width, max_untiled_layer_height));
 
   settings->setFixedPositionCreatesStackingContext(
       fixed_position_creates_stacking_context);
 
   WebNetworkStateNotifier::setOnLine(is_online);
 }
 
 }  // namespace webkit_glue