Identity the mouse pointer type from low-level events for Mac

ui/base/cocoa/base_view.mm

Index: ui/base/cocoa/base_view.mm
diff --git a/ui/base/cocoa/base_view.mm b/ui/base/cocoa/base_view.mm
index ef3eb87f7917d20ce91181ac7f411efb87a9ecb0..9da6f7da1526e88d7f099bcf480edf35d39c0a7e 100644
--- a/ui/base/cocoa/base_view.mm
+++ b/ui/base/cocoa/base_view.mm
@@ -71,6 +71,10 @@ NSString* kSelectionDirection = @"Chromium.kSelectionDirection";
   // This method left intentionally blank.
 }
 
+- (void)tabletEvent:(NSEvent*)theEvent {
+  // This method left intentionally blank.
+}
+
 - (EventHandled)keyEvent:(NSEvent*)theEvent {
   // The default implementation of this method does not handle any key events.
   // Derived classes should return kEventHandled if they handled an event,
@@ -160,6 +164,10 @@ NSString* kSelectionDirection = @"Chromium.kSelectionDirection";
   [self mouseEvent:theEvent];
 }
 
+- (void)tabletProximity:(NSEvent*)theEvent {
+  [self tabletEvent:theEvent];
+}
+
 - (void)keyDown:(NSEvent*)theEvent {
   if ([self keyEvent:theEvent] != kEventHandled)
     [super keyDown:theEvent];