Implement direction-specific touch-action values (blink side)

public/web/WebTouchAction.h

Index: public/web/WebTouchAction.h
diff --git a/public/web/WebTouchAction.h b/public/web/WebTouchAction.h
index 2643199d264f4ecdacb03c77f223c78089fe3a64..27ebe35269fab3d8bba9f859d3e89a8756ccdaa5 100644
--- a/public/web/WebTouchAction.h
+++ b/public/web/WebTouchAction.h
@@ -37,9 +37,13 @@ namespace blink {
 enum WebTouchAction {
     WebTouchActionAuto = 0x0,
     WebTouchActionNone = 0x1,
-    WebTouchActionPanX = 0x2,
-    WebTouchActionPanY = 0x4,
-    WebTouchActionPinchZoom = 0x8,
+    WebTouchActionPanLeft = 0x2,
+    WebTouchActionPanRight = 0x4,
+    WebTouchActionPanX = WebTouchActionPanLeft | WebTouchActionPanRight,
+    WebTouchActionPanUp = 0x8,
+    WebTouchActionPanDown = 0x10,
+    WebTouchActionPanY = WebTouchActionPanUp | WebTouchActionPanDown,
+    WebTouchActionPinchZoom = 0x20,
 };
 inline WebTouchAction operator| (WebTouchAction a, WebTouchAction b) { return WebTouchAction(int(a) | int(b)); }
 inline WebTouchAction& operator|= (WebTouchAction& a, WebTouchAction b) { return a = a | b; }