Allow max aspect ratio to be specified by meta-data tag.

This changelist identifies aspect ratios set via meta-data tags on
the activity or application and applies them to the proper scope.
Values specified via styled attribute take precedence, and values
specified by the activity take priority over values in at the
application level.

Fixes: 63386222
Test: cts/hostsidetests/services/activityandwindowmanager/util/run-test CtsAppTestCases android.app.cts.AspectRatioTests
Test: go/wm-smoke
Change-Id: I0d8d6b2778e7fc12bb9feb85c651e5ec22927f5f