Initialize WorkManager ourself.

This gives us more control over when it happens, as well as lets us set
things like the debug level. Also let's us get rid of the synchronized
block we had in Application#onCreate().

AndroidManifest.xml

@@ -572,6 +572,12 @@
               android:authorities="org.thoughtcrime.securesms.database.attachment"
               android:exported="false" />
 
+    <provider
+              android:name="androidx.work.impl.WorkManagerInitializer"
+              android:authorities="${applicationId}.workmanager-init"
+              android:exported="false"
+              tools:node="remove" />
+
     <receiver android:name=".service.BootReceiver">
         <intent-filter>
             <action android:name="android.intent.action.BOOT_COMPLETED"/>

src/org/thoughtcrime/securesms/ApplicationContext.java

@@ -61,6 +61,7 @@ import java.util.HashSet;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
 
+import androidx.work.Configuration;
 import androidx.work.WorkManager;
 import dagger.ObjectGraph;
 
@@ -80,7 +81,6 @@ public class ApplicationContext extends MultiDexApplication implements Dependenc
   private JobManager             jobManager;
   private ObjectGraph            objectGraph;
   private PersistentLogger       persistentLogger;
-  private boolean                initialized;
 
   private volatile boolean isAppVisible;
 
@@ -90,7 +90,6 @@ public class ApplicationContext extends MultiDexApplication implements Dependenc
 
   @Override
   public void onCreate() {
-    synchronized (this) {
     super.onCreate();
     initializeRandomNumberFix();
     initializeLogging();
@@ -105,18 +104,6 @@ public class ApplicationContext extends MultiDexApplication implements Dependenc
     initializeWebRtc();
     NotificationChannels.create(this);
     ProcessLifecycleOwner.get().getLifecycle().addObserver(this);
-
-      initialized = true;
-      notifyAll();
-    }
-  }
-
-  public void ensureInitialized() {
-    synchronized (this) {
-      while (!initialized) {
-        Util.wait(this, 0);
-      }
-    }
   }
 
   @Override
@@ -172,6 +159,10 @@ public class ApplicationContext extends MultiDexApplication implements Dependenc
   }
 
   private void initializeJobManager() {
+    WorkManager.initialize(this, new Configuration.Builder()
+                                                  .setMinimumLoggingLevel(android.util.Log.DEBUG)
+                                                  .build());
+
     this.jobManager = new JobManager(WorkManager.getInstance());
   }
 

src/org/thoughtcrime/securesms/jobmanager/Job.java

@@ -53,7 +53,6 @@ public abstract class Job extends Worker implements Serializable {
 
     log("doWork()" + logSuffix());
 
-    ApplicationContext.getInstance(getApplicationContext()).ensureInitialized();
     ApplicationContext.getInstance(getApplicationContext()).injectDependencies(this);
 
     if (this instanceof ContextDependent) {