Removed |which| from KeyboardEvent and MouseEvent.

third_party/WebKit/Source/core/events/MouseEvent.cpp

Index: third_party/WebKit/Source/core/events/MouseEvent.cpp
diff --git a/third_party/WebKit/Source/core/events/MouseEvent.cpp b/third_party/WebKit/Source/core/events/MouseEvent.cpp
index c8db6a7220fddfdb07472dbb869ee535aa73ae42..ca606f24d4d90917287efc061d0e19ae4093a9c6 100644
--- a/third_party/WebKit/Source/core/events/MouseEvent.cpp
+++ b/third_party/WebKit/Source/core/events/MouseEvent.cpp
@@ -396,13 +396,13 @@ short MouseEvent::button() const {
   return button_;
 }
 
-int MouseEvent::which() const {
+unsigned MouseEvent::which() const {
   // For the DOM, the return values for left, middle and right mouse buttons are
   // 0, 1, 2, respectively.
   // For the Netscape "which" property, the return values for left, middle and
   // right mouse buttons are 1, 2, 3, respectively.
   // So we must add 1.
-  return button_ + 1;
+  return (unsigned)(button_ + 1);
 }
 
 Node* MouseEvent::toElement() const {