Recognise variable names when parsing CSS property names

third_party/WebKit/Source/core/css/DOMWindowCSS.cpp

Index: third_party/WebKit/Source/core/css/DOMWindowCSS.cpp
diff --git a/third_party/WebKit/Source/core/css/DOMWindowCSS.cpp b/third_party/WebKit/Source/core/css/DOMWindowCSS.cpp
index 763f7b5f17f862e8f955ad0c42b6881d0d803d5a..b0eae0f5d01f81974268fd6386d8c8f1c9eeac80 100644
--- a/third_party/WebKit/Source/core/css/DOMWindowCSS.cpp
+++ b/third_party/WebKit/Source/core/css/DOMWindowCSS.cpp
@@ -33,7 +33,6 @@
 #include "core/css/CSSPropertyMetadata.h"
 #include "core/css/StylePropertySet.h"
 #include "core/css/parser/CSSParser.h"
-#include "core/css/parser/CSSVariableParser.h"
 #include "wtf/text/StringBuilder.h"
 #include "wtf/text/WTFString.h"
 
@@ -42,12 +41,11 @@ namespace blink {
 bool DOMWindowCSS::supports(const String& property, const String& value)
 {
     CSSPropertyID unresolvedProperty = unresolvedCSSPropertyID(property);
-    if (unresolvedProperty == CSSPropertyInvalid) {
-        if (CSSVariableParser::isValidVariableName(property)) {
-            MutableStylePropertySet* dummyStyle = MutableStylePropertySet::create(HTMLStandardMode);
-            return CSSParser::parseValueForCustomProperty(dummyStyle, "--valid", value, false, 0);
-        }
+    if (unresolvedProperty == CSSPropertyInvalid)
         return false;
+    if (unresolvedProperty == CSSPropertyVariable) {
+        MutableStylePropertySet* dummyStyle = MutableStylePropertySet::create(HTMLStandardMode);
+        return CSSParser::parseValueForCustomProperty(dummyStyle, "--valid", value, false, 0);

[ikilpatrick, 2016/08/29 16:30:59]

I assume once we have everything hooked up this will change from "--valid" to
property?

[Timothy Loh, 2016/08/30 03:57:18]

I'm not really sure why this is "--valid" (I guess it's been like that since
custom props were implemented), property should work just as well. I'll probably
have to add logic here for custom props 2 (if CSS.supports is supposed to
change)

     }
 
     ASSERT(CSSPropertyMetadata::isEnabledProperty(unresolvedProperty));