Text selection without trackball.

Backported from HC.

Squashed commit of the following:

commit af214a595c7a9fdd11a2dc384f7d4665abf751c0
    Fixes in TextView's selection.

commit eb9fd59ebe6500a66c2003d46b5802299970ae8d
    TextView with Selection Contextual Mode

commit 4c4c338ef355b369ce4b57d6c6fba7ee8f9dddf4
    Cosmetic changes around TextView.

commit d4b4b054e87480d984ad18766f5e76553e3080d8
    Double and one and a half tap removed from TextView.

commit 897c2847ba1fca8ef01eadadd1bc3de007af3ee5
    Selection handlers in TextView

commit 832be74a5394649e28927484d9a86c6d53b430e7
    New cursor controller in TextViews.

Change-Id: I01cc64736e2abea605317ee53907a1713617fc17