BubbleData [3/n]: separate Bubble view inflation

Allow creating a Bubble and inflating views later. This will be
used to allow BubbleController to create the Bubble object, but
BubbleStackView manage views.

Bug: 123542488
Test: atest BubbleControllerTest
Change-Id: I7bfe608f48a244e03e63ee458069ae10c0d541c3