CSS Custom Properties (Variables)

Source/core/css/StylePropertySet.cpp

Index: Source/core/css/StylePropertySet.cpp
diff --git a/Source/core/css/StylePropertySet.cpp b/Source/core/css/StylePropertySet.cpp
index e7b588b4bb69e3459690728e2bdf7208d76414d5..c2fa5aa2a642921dfde210f6c6f8d53e10fafef7 100644
--- a/Source/core/css/StylePropertySet.cpp
+++ b/Source/core/css/StylePropertySet.cpp
@@ -481,6 +481,17 @@ int MutableStylePropertySet::findPropertyIndex(CSSPropertyID propertyID) const
     return (it == end) ? -1 : it - begin;
 }
 
+unsigned StylePropertySet::variableCount() const
+{
+    ASSERT(RuntimeEnabledFeatures::cssVariablesEnabled());
+    unsigned count = 0;
+    for (unsigned i = 0; i < propertyCount(); ++i) {
+        if (propertyAt(i).id() == CSSPropertyVariable)
+            count++;
+    }
+    return count;
+}
+
 DEFINE_TRACE_AFTER_DISPATCH(MutableStylePropertySet)
 {
 #if ENABLE(OILPAN)