Move fold state listener registration from constructor to start()

If the callback gets called before start() has run, it can NPE

Fixes: 265027517, 264982191
Bug: 265272821
Test: manual and presubmits
Change-Id: Ibb3cb8e0771f3d90cefd56e2308838b28c372ff4

packages/SystemUI/src/com/android/systemui/statusbar/phone/CentralSurfacesImpl.java

@@ -312,6 +312,7 @@ public class CentralSurfacesImpl implements CoreStartable, CentralSurfaces {
 
     private final Context mContext;
     private final LockscreenShadeTransitionController mLockscreenShadeTransitionController;
+    private final DeviceStateManager mDeviceStateManager;
     private CentralSurfacesCommandQueueCallbacks mCommandQueueCallbacks;
     private float mTransitionToFullShadeProgress = 0f;
     private NotificationListContainer mNotifListContainer;
@@ -879,8 +880,7 @@ public class CentralSurfacesImpl implements CoreStartable, CentralSurfaces {
         mMessageRouter.subscribeTo(MSG_LAUNCH_TRANSITION_TIMEOUT,
                 id -> onLaunchTransitionTimeout());
 
-        deviceStateManager.registerCallback(mMainExecutor,
-                new FoldStateListener(mContext, this::onFoldedStateChanged));
+        mDeviceStateManager = deviceStateManager;
         wiredChargingRippleController.registerCallbacks();
 
         mLightRevealScrimViewModelLazy = lightRevealScrimViewModelLazy;
@@ -1069,6 +1069,8 @@ public class CentralSurfacesImpl implements CoreStartable, CentralSurfaces {
             }
         });
 
+        registerCallbacks();
+
         mFalsingManager.addFalsingBeliefListener(mFalsingBeliefListener);
 
         mPluginManager.addPluginListener(
@@ -1123,6 +1125,14 @@ public class CentralSurfacesImpl implements CoreStartable, CentralSurfaces {
                                 requestTopUi, componentTag))));
     }
 
+    @VisibleForTesting
+    /** Registers listeners/callbacks with external dependencies. */
+    void registerCallbacks() {
+        //TODO(b/264502026) move the rest of the listeners here.
+        mDeviceStateManager.registerCallback(mMainExecutor,
+                new FoldStateListener(mContext, this::onFoldedStateChanged));
+    }
+
     @VisibleForTesting
     void initShadeVisibilityListener() {
         mShadeController.setVisibilityListener(new ShadeController.ShadeVisibilityListener() {

packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/CentralSurfacesImplTest.java

@@ -544,6 +544,7 @@ public class CentralSurfacesImplTest extends SysuiTestCase {
         mCentralSurfaces.startKeyguard();
         mInitController.executePostInitTasks();
         notificationLogger.setUpWithContainer(mNotificationListContainer);
+        mCentralSurfaces.registerCallbacks();
     }
 
     @Test