Merge "Fix flaky tests" into oc-dev

services/tests/servicestests/src/com/android/server/wm/WindowTestsBase.java

@@ -115,6 +115,10 @@ class WindowTestsBase {
                 "mChildAppWindowAbove");
         mChildAppWindowBelow = createCommonWindow(mAppWindow, TYPE_APPLICATION_MEDIA_OVERLAY,
                 "mChildAppWindowBelow");
+
+        // Adding a display will cause freezing the display. Make sure to wait until it's unfrozen
+        // to not run into race conditions with the tests.
+        waitUntilHandlersIdle();
     }
 
     @After
@@ -135,6 +139,9 @@ class WindowTestsBase {
             mDisplayContent.removeImmediately();
             sWm.mInputMethodTarget = null;
         }
+
+        // Wait until everything is really cleaned up.
+        waitUntilHandlersIdle();
     }
 
     private WindowState createCommonWindow(WindowState parent, int type, String name) {