bgdexopt: fix deadlock between dump and dexopt thread

- Calling JobScheduler API under mLock leads into accessing
  PMS lock which is held when dump is called from PMS.
  : This leads into deadlock.
- Call JobScheduler outside mLock as that is safe without
  mLock.

Bug: 213945104
Test: run bgdexopt CTS which runs dump and dexopt thread.
Change-Id: I3aabd18e6ec1ec7e158eb008b90dee90b8621c60

services/core/java/com/android/server/pm/BackgroundDexOptService.java

@@ -896,10 +896,10 @@ public final class BackgroundDexOptService {
         synchronized (mLock) {
             if (!mFinishedPostBootUpdate) {
                 mFinishedPostBootUpdate = true;
-                JobScheduler js = mInjector.getJobScheduler();
-                js.cancel(JOB_POST_BOOT_UPDATE);
             }
         }
+        // Safe to do this outside lock.
+        mInjector.getJobScheduler().cancel(JOB_POST_BOOT_UPDATE);
     }
 
     private void notifyPinService(ArraySet<String> updatedPackages) {