Don't handle unitless length quirk in CSS parser fast path

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

Index: third_party/WebKit/Source/core/css/parser/CSSParserFastPaths.cpp
diff --git a/third_party/WebKit/Source/core/css/parser/CSSParserFastPaths.cpp b/third_party/WebKit/Source/core/css/parser/CSSParserFastPaths.cpp
index f8bd98e37ec7dd37955f335aff42f375e53808f1..d1206ece38309489c1c8fb82254af83841625833 100644
--- a/third_party/WebKit/Source/core/css/parser/CSSParserFastPaths.cpp
+++ b/third_party/WebKit/Source/core/css/parser/CSSParserFastPaths.cpp
@@ -109,15 +109,14 @@ static PassRefPtrWillBeRawPtr<CSSValue> parseSimpleLengthValue(CSSPropertyID pro
     }
 
     if (unit == CSSPrimitiveValue::UnitType::Number) {
-        bool quirksMode = isQuirksModeBehavior(cssParserMode);
-        bool svgMode = cssParserMode == SVGAttributeMode;
-        if (number && (!quirksMode && !svgMode))
-            return nullptr;
-        if (svgMode)
+        if (cssParserMode == SVGAttributeMode)
             unit = CSSPrimitiveValue::UnitType::UserUnits;
-        else
+        else if (!number)
             unit = CSSPrimitiveValue::UnitType::Pixels;
+        else
+            return nullptr;
     }
+
     if (number < 0 && !acceptsNegativeNumbers)
         return nullptr;