Remove embedded & document launch always restrictions from a bubble
* No longer need the embedded flag as of ag/9341444
* Instead of requiring the app to specify documentLaunchMode=always we'll
apply the relevant intent flags to force that behaviour; this CL
updates bubble related tests to no longer specify documentLaunchMode or
embedded
* Adds CTS to ensure that an activity in a bubble has the appropriate
flags on the intent
Test: atest NotificationManagerTest
Test: manual - check that CTSVerifierApp still produces bubbles & runs
through the steps correctly
Bug: 138325285
Change-Id: I87ac01139e19e05b6c8caaee166c7ea954ee2592