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
Test: 1. Open a photo in fullscreen mode (hiding navigation bar)
      2. Press power key to bring up keyguard
      3. See if there is "Performed 6 layouts in a row. Skipping" log

Change-Id: Id8c49ac8fc45b98294e48017308dce3117ed1cf8

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

@@ -5743,7 +5743,8 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                     mStatusBarController.updateVisibilityLw(false /*transientAllowed*/,
                             mLastSystemUiFlags, mLastSystemUiFlags);
                 }
-                if (statusBarExpanded && mNavigationBar != null) {
+                final boolean isKeyguardShowing = isStatusBarKeyguard() && !mKeyguardOccluded;
+                if (statusBarExpanded && !isKeyguardShowing && mNavigationBar != null) {
                     if (mNavigationBarController.setBarShowingLw(true)) {
                         changes |= FINISH_LAYOUT_REDO_LAYOUT;
                     }