Tapping mdl-button is not toggling mdl-menu

[AmmarHasan]

Tapping mdl-button associated with mdl-menu is not toggling the menu, however, clicking the button works fine.

On Click:

On Tap:

<button mdl-button #btn1="mdlButton" 
 (click)="m1.toggle($event, btn1)" mdl-button-type="icon" mdl-ripple>
  <mdl-icon>more_vert</mdl-icon>
</button>

<mdl-menu #m1="mdlMenu" mdl-menu-position="bottom-left">
 <mdl-menu-item> Action</mdl-menu-item>
</mdl-menu>