Only increase pending relaunch count if schedule is success

Otherwise the client won't report finishRelaunching to decrease
mPendingRelaunchCount and cause ActivityRecord#isSyncFinished
to return false.

Also skip pre-loading recents(home) if its process is still cached
(e.g. intermediate state when switching user). Otherwise the
transaction may be failed by frozen state.

Bug: 301034389
Test: atest RecentsAnimationTest#testPreloadRecentsActivity
Test: Create multiple users with using different font size, wallpaper,
      dark theme. Launch several apps on each users. Switch between
      the users multiple times. There won't be transition timeout when
      returning from other apps to home.
Merged-In: Ia2761e1e9fadf98ab952440ae884c12cc78697c8
Change-Id: Ia2761e1e9fadf98ab952440ae884c12cc78697c8