Implement frames() timing function

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

Index: third_party/WebKit/Source/core/css/parser/CSSPropertyParser.cpp
diff --git a/third_party/WebKit/Source/core/css/parser/CSSPropertyParser.cpp b/third_party/WebKit/Source/core/css/parser/CSSPropertyParser.cpp
index 74aa3fbf21b20bbf860a9e9468f641f10c2c8a53..6571e77543dce23cab4dc15029f08e211aa9195c 100644
--- a/third_party/WebKit/Source/core/css/parser/CSSPropertyParser.cpp
+++ b/third_party/WebKit/Source/core/css/parser/CSSPropertyParser.cpp
@@ -384,7 +384,7 @@ static CSSValue* consumeTransitionProperty(CSSParserTokenRange& range) {
 }
 
 static CSSValue* consumeSteps(CSSParserTokenRange& range) {
-  ASSERT(range.peek().functionId() == CSSValueSteps);
+  DCHECK_EQ(range.peek().functionId(), CSSValueSteps);
   CSSParserTokenRange rangeCopy = range;
   CSSParserTokenRange args = consumeFunction(rangeCopy);
 
@@ -419,8 +419,28 @@ static CSSValue* consumeSteps(CSSParserTokenRange& range) {
   return CSSStepsTimingFunctionValue::create(steps->getIntValue(), position);
 }
 
+static CSSValue* consumeFrames(CSSParserTokenRange& range) {
+  DCHECK_EQ(range.peek().functionId(), CSSValueFrames);
+  CSSParserTokenRange rangeCopy = range;
+  CSSParserTokenRange args = consumeFunction(rangeCopy);
+
+  CSSPrimitiveValue* frames = consumePositiveInteger(args);
+  if (!frames)
+    return nullptr;
+
+  int framesInt = frames->getIntValue();
+  if (framesInt <= 1)
+    return nullptr;
+
+  if (!args.atEnd())
+    return nullptr;
+
+  range = rangeCopy;
+  return CSSFramesTimingFunctionValue::create(framesInt);
+}
+
 static CSSValue* consumeCubicBezier(CSSParserTokenRange& range) {
-  ASSERT(range.peek().functionId() == CSSValueCubicBezier);
+  DCHECK_EQ(range.peek().functionId(), CSSValueCubicBezier);
   CSSParserTokenRange rangeCopy = range;
   CSSParserTokenRange args = consumeFunction(rangeCopy);
 
@@ -448,6 +468,8 @@ static CSSValue* consumeAnimationTimingFunction(CSSParserTokenRange& range) {
   CSSValueID function = range.peek().functionId();
   if (function == CSSValueSteps)
     return consumeSteps(range);
+  if (function == CSSValueFrames)
+    return consumeFrames(range);
   if (function == CSSValueCubicBezier)
     return consumeCubicBezier(range);
   return nullptr;