Merge "Factor freqeuncy and mimetype of past sharings, foreground app into...

Merge "Factor freqeuncy and mimetype of past sharings, foreground app into sharesheet model. Promote most frequent sharable apps to tackle cold start issue when device doesn't hold enough sharing history." into rvc-dev am: 7abd9be7 am: 68cea0b1

Change-Id: I9138048638ffd1f18465d6c016e897c5ad404020