Define DOM_KEY_LOCATION_* constants on KeyboardEvent

Source/core/dom/KeyboardEvent.idl

Index: Source/core/dom/KeyboardEvent.idl
diff --git a/Source/core/dom/KeyboardEvent.idl b/Source/core/dom/KeyboardEvent.idl
index cda219fa046a5e9267bf90a8bc30adc1e560042e..dd76eb9c838d15ff1305300a3eb0958a6e5ae8f5 100644
--- a/Source/core/dom/KeyboardEvent.idl
+++ b/Source/core/dom/KeyboardEvent.idl
@@ -21,6 +21,12 @@
 [
     ConstructorTemplate=Event
 ] interface KeyboardEvent : UIEvent {
+    const unsigned long DOM_KEY_LOCATION_STANDARD = 0x00;
+    const unsigned long DOM_KEY_LOCATION_LEFT     = 0x01;
+    const unsigned long DOM_KEY_LOCATION_RIGHT    = 0x02;
+    const unsigned long DOM_KEY_LOCATION_NUMPAD   = 0x03;
+    const unsigned long DOM_KEY_LOCATION_MOBILE   = 0x04;
+    const unsigned long DOM_KEY_LOCATION_JOYSTICK = 0x05;
 
     [InitializedByEventConstructor] readonly attribute DOMString        keyIdentifier;
     [InitializedByEventConstructor] readonly attribute unsigned long    keyLocation;