An existing activity may be relaunched when moving from background
to front if the current configuration is changed and the activity
cannot handle the change.
The relaunch type was reported as a hot start because its process
is alive and the original activity exists. But the relaunch needs to
destroy the original activity and create a new instance, which may
even take longer time than a warm start. So the case should be
separated from hot start.
Also:
- Make WaitResult#launchState is always populated by
ActivityMetricsLogger, so "am start -W" can get consistent
launch type.
- Remove dead code in ActivityRecord#ensureActivityConfiguration
that it already early returns if !attachedToProcess.
Bug: 172528316
Test: atest ActivityMetricsLaunchObserverTests#testLaunchState
Change-Id: I3ef64ce1e23b2f13d42fa2b12bc31c0cdb4652fc
59c2e7cf8a