Added parseShorthand method from the parser to CSSPropertyAPI.h.

third_party/WebKit/Source/core/css/properties/CSSPropertyAPI.h

 // 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.
 
 #ifndef CSSPropertyAPI_h
 #define CSSPropertyAPI_h
 
 #include "core/CSSPropertyNames.h"
 #include "wtf/Allocator.h"
 
 namespace blink {
 
 class CSSValue;
 class CSSParserContext;
 class CSSParserTokenRange;
 
 // We will use this API to represent all functions used for property-specific
 // logic inside the blink style engine. All specific properties are subclasses
 // of CSSPropertyAPI.
 //
 // To add a new property using this API:
 // - Make a class that implements CSSPropertyAPI, and implement the static
 //   methods.
-// - Update the cssPropertyDescriptors array in CSSPropertyDescriptor.cpp to
-//   call GET_DESCRIPTOR(classname).
+// - Add the api_class flag to the property CSSProperties.in file, with an
+//   optional class name for grouped properties.
 //
 // To add new functions using this API:
-// - New functions and static variables can be added in this class. A default
-//   implementation of functions can optionally be provided.
-// - When adding new functions, also add them to GET_DESCRIPTOR, and the get()
-//   method in CSSPropertyDescriptors.cpp, and the descriptor struct in
-//   CSSPropertyDescriptor.h.
+// - New functions and static variables can be added in this class.
+// - When adding new functions, also add them to the initializer list in
+//   the cssPropertyDescriptors in CSSPropertyDescriptor.cpp.tmpl, and add a
+//   nullptr to the invalid CSSPropertyDescriptor.
+
 class CSSPropertyAPI {
   STATIC_ONLY(CSSPropertyAPI);
 
  public:
   // Parses a single CSS property and returns the corresponding CSSValue. If the
   // input is invalid it returns nullptr.
   static const CSSValue* parseSingleValue(CSSParserTokenRange&,
-                                          const CSSParserContext*);
+                                          const CSSParserContext*) {
+    NOTREACHED();
+    return nullptr;
+  }
+
+  static bool parseShorthand(bool,
+                             CSSParserTokenRange&,
+                             const CSSParserContext*) {
+    NOTREACHED();
+    return false;
+  }
 };
 
 }  // namespace blink
 
 #endif  // CSSPropertyAPI_h