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

public/web/WebTouchAction.h

Index: public/web/WebTouchAction.h
diff --git a/public/web/WebTouchAction.h b/public/web/WebTouchAction.h
old mode 100644
new mode 100755
index 4a07de2e747d3323ec7d980658523c37ef407814..fde3c1fc3759149a01cb2f832d52be7c55a75444
--- a/public/web/WebTouchAction.h
+++ b/public/web/WebTouchAction.h
@@ -35,9 +35,16 @@ namespace blink {
 
 // Flags for permitted touch actions, specified in http://www.w3.org/TR/pointerevents/#the-touch-action-css-property.
 enum WebTouchAction {
-    WebTouchActionNone = 0,
-    WebTouchActionAuto
+    WebTouchActionAuto = 0x0,
+    WebTouchActionNone =  0x1,

[vivekg, 2013/12/13 14:14:31]

nit: Extra space here..

Also we are now assigning WebTouchActionNone = 1 which earlier was = 0. Will it
cause any issue elsewhere? 

The enum values like this are defined as below elsewhere in the blink source.
Should we also align to the same? 

enum WebTouchAction {
    WebTouchActionAuto = 1 << 0,
    WebTouchActionNone = 1 << 1,
    ...
}

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

auto is a default value for any element for touch-action when not specified.
Thats the reason i changed it. It will not cause any issue.
in RenderStyleConstants.h there are other enum which are similar to this one. so
i think it aligns and should not be issue in blink.

Done.

+    WebTouchActionPanX = 0x2,
+    WebTouchActionPanY = 0x4
 };
+inline WebTouchAction operator| (WebTouchAction a, WebTouchAction b) { return WebTouchAction(int(a) | int(b)); }
+inline WebTouchAction& operator|= (WebTouchAction& a, WebTouchAction b) { return a = a | b; }
+inline WebTouchAction operator& (WebTouchAction a, WebTouchAction b) { return WebTouchAction(int(a) & int(b)); }
+inline WebTouchAction& operator&= (WebTouchAction& a, WebTouchAction b) { return a = a & b; }
+
 
 } // namespace blink