Fix NullPointerException for WifiDisplayController.

Set WifiDisplay to unavailable if p2p device is unavailable,
because the approach of WifiP2pWfdInfo.getWfdInfo() maybe return null,
so we need to do a non-null check to ensure the NPE issue will not
happen.

Bug: 297799091

Test: atest FrameworksWifiApiTests

Change-Id: I06e77719e646a28cc40e1e3d7c45b4f3c9472673
Signed-off-by: jiayongqiang <jiayongqiang@xiaomi.com>
diff --git a/services/core/java/com/android/server/display/WifiDisplayController.java b/services/core/java/com/android/server/display/WifiDisplayController.java
index cd36dd0..04ae13f 100644
--- a/services/core/java/com/android/server/display/WifiDisplayController.java
+++ b/services/core/java/com/android/server/display/WifiDisplayController.java
@@ -1062,8 +1062,10 @@
     }
 
     private static WifiDisplay createWifiDisplay(WifiP2pDevice device) {
+        WifiP2pWfdInfo wfdInfo = device.getWfdInfo();
+        boolean isSessionAvailable = wfdInfo != null && wfdInfo.isSessionAvailable();
         return new WifiDisplay(device.deviceAddress, device.deviceName, null,
-                true, device.getWfdInfo().isSessionAvailable(), false);
+                true, isSessionAvailable, false);
     }
 
     private final BroadcastReceiver mWifiP2pReceiver = new BroadcastReceiver() {