CSS Custom Properties: Angles do not support unitless 0

third_party/WebKit/Source/core/css/CSSSyntaxDescriptor.cpp

 // Copyright 2016 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 "core/css/CSSSyntaxDescriptor.h"
 
 #include "core/animation/CSSColorInterpolationType.h"
 #include "core/animation/CSSLengthInterpolationType.h"
 #include "core/animation/CSSValueInterpolationType.h"
 #include "core/css/CSSCustomPropertyDeclaration.h"
@@ skipping 146 matching lines @@
     case CSSSyntaxType::kColor:
       return ConsumeColor(range, kHTMLStandardMode);
     case CSSSyntaxType::kImage:
       return ConsumeImage(range, context);
     case CSSSyntaxType::kUrl:
       return ConsumeUrl(range, context);
     case CSSSyntaxType::kInteger:
       return ConsumeInteger(range);
     case CSSSyntaxType::kAngle:
       return ConsumeAngle(range, *context,
-                          UseCounter::kUnitlessZeroAngleCustomProperty);
+                          WTF::Optional<UseCounter::Feature>());
     case CSSSyntaxType::kTime:
       return ConsumeTime(range, ValueRange::kValueRangeAll);
     case CSSSyntaxType::kResolution:
       return ConsumeResolution(range);
     case CSSSyntaxType::kTransformFunction:
       return nullptr;  // TODO(timloh): Implement this.
     case CSSSyntaxType::kCustomIdent:
       return ConsumeCustomIdent(range);
     default:
       NOTREACHED();
@@ skipping 32 matching lines @@
   for (const CSSSyntaxComponent& component : syntax_components_) {
     if (const CSSValue* result =
             ConsumeSyntaxComponent(component, range, context))
       return result;
   }
   return CSSVariableParser::ParseRegisteredPropertyValue(range, *context, true,
                                                          is_animation_tainted);
 }
 
 }  // namespace blink