Fix FloatingToolbar.show()

*Finer cancel animation methods so we call only the necessary ones.

*Don't set the FloatingToolbarPopup content view's alpha to 0
 before showing it's popup window.

*FloatingToolbarPopup.dismiss() should run when toolbar is hidden.

Bug: 20456876
Change-Id: I2e7ff5f2ec56af2def0976fa8e770c651daaa3a3