Don't lock WM when calling ActivityStackSupervisor.resolveIntent()

In startActivities, now WM lock is only acquired on the execution of
activity starter. This fixes the deadlock from startActivitiesAsPackage
that locks WM then AM (in PackageManagerService.resolveIntentInternal).

Fixes: 123934974
Test: Manual - Long press an app icon to add a shortcut and launch it.
      (That invokes ILauncherApps.startShortcut -> startActivities)

Change-Id: Ief8d6eeeba40d33d2853df69b9a090abbf06b32f