add pan-x and pan-y support to CSS touch-action parsing.

Source/core/css/CSSComputedStyleDeclaration.cpp

Index: Source/core/css/CSSComputedStyleDeclaration.cpp
diff --git a/Source/core/css/CSSComputedStyleDeclaration.cpp b/Source/core/css/CSSComputedStyleDeclaration.cpp
old mode 100644
new mode 100755
index 73ce88040017a04f9e847fd5e69f1ba4002e2ce4..41b017b3a5208c0194780edab92cf45869fff862
--- a/Source/core/css/CSSComputedStyleDeclaration.cpp
+++ b/Source/core/css/CSSComputedStyleDeclaration.cpp
@@ -1547,6 +1547,30 @@ static PassRefPtr<CSSPrimitiveValue> valueForFontWeight(RenderStyle& style)
     return cssValuePool().createIdentifierValue(CSSValueNormal);
 }
 
+static PassRefPtr<CSSValue> touchActionFlagsToCSSValue(TouchAction touchAction)
+{
+    RefPtr<CSSValueList> list = CSSValueList::createSpaceSeparated();
+    if (touchAction == TouchActionAuto) {
+        list->append(cssValuePool().createIdentifierValue(CSSValueAuto));
+    }
+    if (touchAction & TouchActionNone) {
+        ASSERT(touchAction == TouchActionNone);
+        list->append(cssValuePool().createIdentifierValue(CSSValueNone));
+    }
+    if (touchAction & TouchActionPanX) {
+        list->append(cssValuePool().createIdentifierValue(CSSValuePanX));
+    }
+    if (touchAction & TouchActionPanY) {
+        list->append(cssValuePool().createIdentifierValue(CSSValuePanY));
+    }
+
+    if (!list->length()) {
+        ASSERT(false);
+        return cssValuePool().createIdentifierValue(CSSValueAuto);

[Rick Byers, 2013/12/13 13:34:23]

nit: just remove this whole if block and just ASSERT(list->length()) - we'll
never get here, so it's not worth worrying about a fallback.

[gnana, 2013/12/13 17:06:23]

Done.

+    }
+    return list.release();
+}
+
 static bool isLayoutDependent(CSSPropertyID propertyID, PassRefPtr<RenderStyle> style, RenderObject* renderer)
 {
     // Some properties only depend on layout in certain conditions which
@@ -2321,7 +2345,7 @@ PassRefPtr<CSSValue> CSSComputedStyleDeclaration::getPropertyCSSValue(CSSPropert
         case CSSPropertyTop:
             return valueForPositionOffset(*style, CSSPropertyTop, renderer, m_node->document().renderView());
         case CSSPropertyTouchAction:
-            return cssValuePool().createValue(style->touchAction());
+            return touchActionFlagsToCSSValue(style->touchAction());
         case CSSPropertyTouchActionDelay:
             return cssValuePool().createValue(style->touchActionDelay());
         case CSSPropertyUnicodeBidi: