Wrapped call to notifyAll() in a synchronized block

Change-Id: I452caa56bef4541b53917bdd6f22034161255dd1
Bug: 7118468

Author: the-felipeal

cmds/am/src/com/android/commands/am/Am.java

@@ -1188,8 +1188,10 @@ public void performReceive(Intent intent, int resultCode, String data, Bundle ex
             if (data != null) line = line + ", data=\"" + data + "\"";
             if (extras != null) line = line + ", extras: " + extras;
             System.out.println(line);
-            mFinished = true;
-            notifyAll();
+            synchronized (this) {
+              mFinished = true;
+              notifyAll();
+            }
         }
 
         public synchronized void waitForFinish() {