[Mac] Enter should trigger the buttons in the new avatar bubble.

chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm

Index: chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm
diff --git a/chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm b/chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm
index 621a6e705f09b390bb4a6a95a83b5069f55adc39..4ab33ac13e05b690de28f0eb6a6655d0cbefbf78 100644
--- a/chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm
+++ b/chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm
@@ -36,6 +36,7 @@
 #include "chrome/browser/ui/chrome_style.h"
 #import "chrome/browser/ui/cocoa/info_bubble_view.h"
 #import "chrome/browser/ui/cocoa/info_bubble_window.h"
+#import "chrome/browser/ui/cocoa/key_equivalent_constants.h"
 #import "chrome/browser/ui/cocoa/profiles/user_manager_mac.h"
 #include "chrome/browser/ui/singleton_tabs.h"
 #include "chrome/browser/ui/user_manager.h"
@@ -2100,6 +2101,7 @@ class ActiveProfileObserverBridge : public AvatarMenuObserver,
   [button setBordered:NO];
   [button setTarget:self];
   [button setAction:action];
+  [button setKeyEquivalent:kKeyEquivalentReturn];
 
   return button.autorelease();
 }