Prevent infinite layout while hiding nav bar on keyguard

By the original logic, if there is a focused window which hides
navigation bar while keyguard is showing, PhoneWindowManager would
hide/show navigation bar frequently, which caused infinite layout.

Bug: 78681867
Bug: 79896018
Bug: 80113279
Test: 1. a. Open a photo in fullscreen mode (hiding navigation bar)
         b. Press power key to bring up keyguard
         c. See if there is "Performed 6 layouts in a row. Skipping"
            log
      2. go/wm-smoke
      3. Open a video in YouTube in fullscreen mode and then expand
         status bar, and see if navigation bar would show; collapse
	 status bar, and see if navigation bar would hide

Change-Id: Id8c49ac8fc45b98294e48017308dce3117ed1cf8
Merged-In: Id8c49ac8fc45b98294e48017308dce3117ed1cf8
(cherry picked from commit 53e8cfe794)

services/core/java/com/android/server/policy/PhoneWindowManager.java

@@ -5761,11 +5761,6 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                     mStatusBarController.updateVisibilityLw(false /*transientAllowed*/,
                             mLastSystemUiFlags, mLastSystemUiFlags);
                 }
-                if (statusBarExpanded && mNavigationBar != null) {
-                    if (mNavigationBarController.setBarShowingLw(true)) {
-                        changes |= FINISH_LAYOUT_REDO_LAYOUT;
-                    }
-                }
             } else if (mTopFullscreenOpaqueWindowState != null) {
                 topIsFullscreen = topAppHidesStatusBar;
                 // The subtle difference between the window for mTopFullscreenOpaqueWindowState