Made CSSPropertyAPIWillChange which implements API for will-change

Made implementation of CSSPropertyAPI for the will change property. The
logic for this was taken out of CSSPropertyParser.cpp and moved into
CSSPropertyAPIWillChange.cpp.

Also fixed error in CSSPropertyDescriptor.cpp.tmpl which meant only one
class could be implemented (missing comma in array).

BUG=668012

Review-Url: https://codereview.chromium.org/2550313003
Cr-Commit-Position: refs/heads/master@{#439387}

third_party/WebKit/Source/build/scripts/templates/CSSPropertyDescriptor.cpp.tmpl

@@ -21,7 +21,7 @@ static CSSPropertyDescriptor cssPropertyDescriptors[] = {
     // When functions are added to CSSPropertyAPI, also add them to the struct
     // initaliser below.
     {% for api_class in api_classes %}
-    { {{api_class.classname}}::parseSingleValue, true }
+    { {{api_class.classname}}::parseSingleValue, true },
     {% endfor %}
 };
 

third_party/WebKit/Source/core/css/BUILD.gn

@@ -344,6 +344,7 @@ blink_core_sources("css") {
     "parser/SizesCalcParser.cpp",
     "properties/CSSPropertyAPI.h",
     "properties/CSSPropertyAPIWebkitPadding.cpp",
+    "properties/CSSPropertyAPIWillChange.cpp",
     "properties/CSSPropertyDescriptor.h",
     "resolver/AnimatedStyleBuilder.cpp",
     "resolver/AnimatedStyleBuilder.h",

third_party/WebKit/Source/core/css/CSSProperties.in

@@ -457,7 +457,7 @@ user-select inherited
 white-space inherited, independent, keyword_only, keywords=[normal|pre|pre-wrap|pre-line|nowrap|-webkit-nowrap], initial_keyword=normal
 widows interpolable, inherited, type_name=short
 width interpolable, initial=initialSize, converter=convertLengthSizing, typedom_types=[Length], keywords=[auto], supports_percentage
-will-change custom_all
+will-change custom_all, api_class
 word-break inherited
 word-spacing interpolable, inherited, initial=initialLetterWordSpacing, converter=convertSpacing
 // UAs must treat 'word-wrap' as an alternate name for the 'overflow-wrap' property. So using the same handlers.

third_party/WebKit/Source/core/css/parser/CSSPropertyParser.cpp

@@ -302,57 +302,6 @@ static CSSValueList* consumeTransformOrigin(CSSParserTokenRange& range,
   return nullptr;
 }
 
-// Methods for consuming non-shorthand properties starts here.
-static CSSValue* consumeWillChange(CSSParserTokenRange& range) {
-  if (range.peek().id() == CSSValueAuto)
-    return consumeIdent(range);
-
-  CSSValueList* values = CSSValueList::createCommaSeparated();
-  // Every comma-separated list of identifiers is a valid will-change value,
-  // unless the list includes an explicitly disallowed identifier.
-  while (true) {
-    if (range.peek().type() != IdentToken)
-      return nullptr;
-    CSSPropertyID unresolvedProperty =
-        unresolvedCSSPropertyID(range.peek().value());
-    if (unresolvedProperty != CSSPropertyInvalid &&
-        unresolvedProperty != CSSPropertyVariable) {
-      ASSERT(CSSPropertyMetadata::isEnabledProperty(unresolvedProperty));
-      // Now "all" is used by both CSSValue and CSSPropertyValue.
-      // Need to return nullptr when currentValue is CSSPropertyAll.
-      if (unresolvedProperty == CSSPropertyWillChange ||
-          unresolvedProperty == CSSPropertyAll)
-        return nullptr;
-      values->append(*CSSCustomIdentValue::create(unresolvedProperty));
-      range.consumeIncludingWhitespace();
-    } else {
-      switch (range.peek().id()) {
-        case CSSValueNone:
-        case CSSValueAll:
-        case CSSValueAuto:
-        case CSSValueDefault:
-        case CSSValueInitial:
-        case CSSValueInherit:
-          return nullptr;
-        case CSSValueContents:
-        case CSSValueScrollPosition:
-          values->append(*consumeIdent(range));
-          break;
-        default:
-          range.consumeIncludingWhitespace();
-          break;
-      }
-    }
-
-    if (range.atEnd())
-      break;
-    if (!consumeCommaIncludingWhitespace(range))
-      return nullptr;
-  }
-
-  return values;
-}
-
 static CSSFontFeatureValue* consumeFontFeatureTag(CSSParserTokenRange& range) {
   // Feature tag name consists of 4-letter characters.
   static const unsigned tagNameLength = 4;
@@ -3484,8 +3433,6 @@ const CSSValue* CSSPropertyParser::parseSingleValue(
     return cssPropertyDesc.parseSingleValue(m_range, m_context);
 
   switch (property) {
-    case CSSPropertyWillChange:
-      return consumeWillChange(m_range);
     case CSSPropertyPage:
       return consumePage(m_range);
     case CSSPropertyQuotes:

third_party/WebKit/Source/core/css/properties/CSSPropertyAPIWillChange.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/properties/CSSPropertyAPIWillChange.h"
+
+#include "core/css/CSSValueList.h"
+#include "core/css/parser/CSSParserTokenRange.h"
+#include "core/css/parser/CSSPropertyParser.h"
+#include "core/css/parser/CSSPropertyParserHelpers.h"
+
+namespace blink {
+
+const CSSValue* CSSPropertyAPIWillChange::parseSingleValue(
+    CSSParserTokenRange& range,
+    const CSSParserContext& context) {
+  if (range.peek().id() == CSSValueAuto)
+    return CSSPropertyParserHelpers::consumeIdent(range);
+
+  CSSValueList* values = CSSValueList::createCommaSeparated();
+  // Every comma-separated list of identifiers is a valid will-change value,
+  // unless the list includes an explicitly disallowed identifier.
+  while (true) {
+    if (range.peek().type() != IdentToken)
+      return nullptr;
+    CSSPropertyID unresolvedProperty =
+        unresolvedCSSPropertyID(range.peek().value());
+    if (unresolvedProperty != CSSPropertyInvalid &&
+        unresolvedProperty != CSSPropertyVariable) {
+      DCHECK(CSSPropertyMetadata::isEnabledProperty(unresolvedProperty));
+      // Now "all" is used by both CSSValue and CSSPropertyValue.
+      // Need to return nullptr when currentValue is CSSPropertyAll.
+      if (unresolvedProperty == CSSPropertyWillChange ||
+          unresolvedProperty == CSSPropertyAll)
+        return nullptr;
+      values->append(*CSSCustomIdentValue::create(unresolvedProperty));
+      range.consumeIncludingWhitespace();
+    } else {
+      switch (range.peek().id()) {
+        case CSSValueNone:
+        case CSSValueAll:
+        case CSSValueAuto:
+        case CSSValueDefault:
+        case CSSValueInitial:
+        case CSSValueInherit:
+          return nullptr;
+        case CSSValueContents:
+        case CSSValueScrollPosition:
+          values->append(*CSSPropertyParserHelpers::consumeIdent(range));
+          break;
+        default:
+          range.consumeIncludingWhitespace();
+          break;
+      }
+    }
+
+    if (range.atEnd())
+      break;
+    if (!CSSPropertyParserHelpers::consumeCommaIncludingWhitespace(range))
+      return nullptr;
+  }
+
+  return values;
+}
+
+}  // namespace blink