Make CSSValuePair store const CSSValues

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

Index: third_party/WebKit/Source/core/css/CSSGradientValue.cpp
diff --git a/third_party/WebKit/Source/core/css/CSSGradientValue.cpp b/third_party/WebKit/Source/core/css/CSSGradientValue.cpp
index 57a1683cfa39ceccfb4a830ad588ec063c55f3a4..e435a72333209bad6c92221f68fc158822418bad 100644
--- a/third_party/WebKit/Source/core/css/CSSGradientValue.cpp
+++ b/third_party/WebKit/Source/core/css/CSSGradientValue.cpp
@@ -481,7 +481,7 @@ void CSSGradientValue::addStops(Gradient* gradient, const CSSToLengthConversionD
     }
 }
 
-static float positionFromValue(CSSValue* value, const CSSToLengthConversionData& conversionData, const IntSize& size, bool isHorizontal)
+static float positionFromValue(const CSSValue* value, const CSSToLengthConversionData& conversionData, const IntSize& size, bool isHorizontal)
 {
     int origin = 0;
     int sign = 1;
@@ -489,10 +489,11 @@ static float positionFromValue(CSSValue* value, const CSSToLengthConversionData&
 
     // In this case the center of the gradient is given relative to an edge in the form of:
     // [ top | bottom | right | left ] [ <percentage> | <length> ].
+    const CSSValue* localValue = value;

[nainar, 2016/07/18 01:47:00]

As per IRL conversation we can just modify value as we were doing before. There
shouldn't be any need to add a new local variable. 

But good to go other than that!

     if (value->isValuePair()) {
-        CSSValuePair& pair = toCSSValuePair(*value);
+        const CSSValuePair& pair = toCSSValuePair(*value);
         CSSValueID originID = toCSSPrimitiveValue(pair.first()).getValueID();
-        value = &pair.second();
+        localValue = &pair.second();
 
         if (originID == CSSValueRight || originID == CSSValueBottom) {
             // For right/bottom, the offset is relative to the far edge.
@@ -501,7 +502,7 @@ static float positionFromValue(CSSValue* value, const CSSToLengthConversionData&
         }
     }
 
-    CSSPrimitiveValue* primitiveValue = toCSSPrimitiveValue(value);
+    const CSSPrimitiveValue* primitiveValue = toCSSPrimitiveValue(localValue);
 
     if (primitiveValue->isNumber())
         return origin + sign * primitiveValue->getFloatValue() * conversionData.zoom();