root/chrome/android/java/src/org/chromium/chrome/browser/appmenu/

[..]
  1. AppMenu.java
  2. AppMenuAdapter.java
  3. AppMenuButtonHelper.java
  4. AppMenuDragHelper.java
  5. AppMenuHandler.java
  6. AppMenuItemIcon.java
  7. AppMenuObserver.java
  8. AppMenuPropertiesDelegate.java
[..]