Prevent NullPointerException and remove unsed variable

Bug: 234093736
Test: presubmit
Change-Id: Id4298f3af970cba0608960bcac21c141bb2d99aa

core/tests/coretests/src/android/view/SurfaceControlViewHostInsetsTest.java

@@ -69,7 +69,6 @@ public class SurfaceControlViewHostInsetsTest {
 
     private InsetsState statusBarState(boolean visible) {
         final InsetsState insetsState = new InsetsState();
-        final int id = InsetsSource.createId(null /* owner */, 0 /* index */, statusBars());
         insetsState.setDisplayFrame(new Rect(0, 0, 1000, 1000));
         insetsState.getOrCreateSource(
                 InsetsSource.createId(null /* owner */, 0 /* index */, statusBars()), statusBars())

services/core/java/com/android/server/wm/InsetsPolicy.java

@@ -635,6 +635,12 @@ class InsetsPolicy {
         final SparseArray<InsetsSourceControl> controlsReady = new SparseArray<>();
         final InsetsSourceControl[] controls =
                 mStateController.getControlsForDispatch(mDummyControlTarget);
+        if (controls == null) {
+            if (callback != null) {
+                DisplayThread.getHandler().post(callback);
+            }
+            return;
+        }
         for (InsetsSourceControl control : controls) {
             if (isTransient(control.getType()) && control.getLeash() != null) {
                 typesReady |= control.getType();