Move fake menu buttons to DialtactsActivity

Currenty fake menu buttons are in DialpadFragment, which requires the app
to render split ActionBars during users drag events. Because of that
we have a rendering problem around horizontal swipes (bug 6126934: Lots
of stutter in animations between Dialer tabs).

This change moves those buttons to DialtactsActivity and delay menu
creation until really necessary.

This change also introduces some verbose logs, to detect possible new
problems or bug 6041917.

Bug: 6041917
Bug: 6126934
Change-Id: Ic2d8d82461e6d1916f2309b775f47c47d310ad1a