Emit console warning when element.animate() keyframe value fails to parse

third_party/WebKit/Source/core/animation/StringKeyframe.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 StringKeyframe_h
 #define StringKeyframe_h
 
 #include "core/animation/Keyframe.h"
 #include "core/css/StylePropertySet.h"
 
 #include "wtf/HashMap.h"
 
 namespace blink {
 
 class StyleSheetContents;
 
 // A specialization of Keyframe that associates user specified keyframe
 // properties with either CSS properties or SVG attributes.
 class StringKeyframe : public Keyframe {
  public:
   static PassRefPtr<StringKeyframe> create() {
     return adoptRef(new StringKeyframe);
   }
 
-  void setCSSPropertyValue(const AtomicString& propertyName,
-                           const String& value,
-                           StyleSheetContents*);
-  void setCSSPropertyValue(CSSPropertyID,
-                           const String& value,
-                           StyleSheetContents*);
+  MutableStylePropertySet::SetResult setCSSPropertyValue(
+      const AtomicString& propertyName,
+      const String& value,
+      StyleSheetContents*);
+  MutableStylePropertySet::SetResult setCSSPropertyValue(CSSPropertyID,
+                                                         const String& value,
+                                                         StyleSheetContents*);
   void setCSSPropertyValue(CSSPropertyID, const CSSValue&);
   void setPresentationAttributeValue(CSSPropertyID,
                                      const String& value,
                                      StyleSheetContents*);
   void setSVGAttributeValue(const QualifiedName&, const String& value);
 
   const CSSValue& cssPropertyValue(const PropertyHandle& property) const {
     int index = -1;
     if (property.isCSSCustomProperty())
       index =
@@ skipping 138 matching lines @@
                   value.isCSSPropertySpecificKeyframe());
 DEFINE_TYPE_CASTS(SVGPropertySpecificKeyframe,
                   Keyframe::PropertySpecificKeyframe,
                   value,
                   value->isSVGPropertySpecificKeyframe(),
                   value.isSVGPropertySpecificKeyframe());
 
 }  // namespace blink
 
 #endif