Implemented RuleSet diff for active stylesheets.

third_party/WebKit/Source/core/BUILD.gn

 # 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.
 
 import("//build/config/chromecast_build.gni")
 import("//build/config/ui.gni")
 import("//build/split_static_library.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 import("//third_party/WebKit/Source/bindings/bindings.gni")
 import("//third_party/WebKit/Source/bindings/modules/modules.gni")
@@ skipping 921 matching lines @@
     "animation/animatable/AnimatableDoubleAndBoolTest.cpp",
     "animation/animatable/AnimatableDoubleTest.cpp",
     "animation/animatable/AnimatableLengthTest.cpp",
     "animation/animatable/AnimatableNeutralTest.cpp",
     "animation/animatable/AnimatableStrokeDasharrayListTest.cpp",
     "animation/animatable/AnimatableUnknownTest.cpp",
     "animation/animatable/AnimatableValueTestHelper.cpp",
     "animation/animatable/AnimatableValueTestHelper.h",
     "animation/animatable/AnimatableValueTestHelperTest.cpp",
     "clipboard/DataObjectTest.cpp",
+    "css/ActiveStyleSheetsTest.cpp",
     "css/AffectedByFocusTest.cpp",
     "css/CSSCalculationValueTest.cpp",
     "css/CSSFontFaceSourceTest.cpp",
     "css/CSSPageRuleTest.cpp",
     "css/CSSSelectorTest.cpp",
     "css/CSSStyleDeclarationTest.cpp",
     "css/CSSStyleSheetResourceTest.cpp",
     "css/CSSTestHelper.cpp",
     "css/CSSTestHelper.h",
     "css/CSSValueTestHelper.h",
@@ skipping 271 matching lines @@
   sources = [
     "html/parser/HTMLPreloadScannerFuzzer.cpp",
     "html/parser/TextResourceDecoderForFuzzing.h",
   ]
   seed_corpus = "//third_party/WebKit/LayoutTests/fast/parser"
   deps = [
     ":core",
     "../platform:blink_fuzzer_test_support",
   ]
 }