Create interface and data to pass bubble updates to launcher

1) Create a common folder for bubbles in wm shell so that we can share
data between shell and launcher, the information shared will be:

- BubbleBarUpdate - a specific change in bubble state that launcher
  can use to update the bubble bar, the update will be created via
  the BubbleData.Update object
- BubbleInfo - an object representing the necessary information to
  render a bubble, BubbleInfo can be created via a Bubble object
- RemovedBubble - an object representing a removed bubble

2) Create a two aidl interfaces allowing launcher to register a
listener to get notified of BubbleBarUpdates and to notify WMShell
of UI interactions with the bubble bar so that shell can show or hide
the TaskView associated with the bubble.

3) Create the impl of the aidl interfaces in BubbleController

4) The listener is only registered if the flag is active

Bug: 253318833
Test: treehugger / manual with other CLs
Change-Id: I0955772db2502d99367e793d3e2cb229d31bd7b7