Fix leaked windows exception in WifiDialogActivity

WifiDialog was created by WifiDialogActivity.
If activity was destroyed suddenly, WifiDialog can't dismiss itself.

So, we need to dismiss dialog, when activity was destroyed.

Test: robo and manual test
Bug: 111841375
Change-Id: I8aaf1c78e72144bf7c9cbc2392bce30e715d86e9

src/com/android/settings/wifi/WifiDialogActivity.java

@@ -52,6 +52,8 @@ public class WifiDialogActivity extends Activity implements WifiDialog.WifiDialo
     @VisibleForTesting
     static final String KEY_CONNECT_FOR_CALLER = "connect_for_caller";
 
+    private WifiDialog mDialog;
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         final Intent intent = getIntent();
@@ -67,10 +69,10 @@ public class WifiDialogActivity extends Activity implements WifiDialog.WifiDialo
             accessPoint = new AccessPoint(this, accessPointState);
         }
 
-        WifiDialog dialog = WifiDialog.createModal(
+        mDialog = WifiDialog.createModal(
                 this, this, accessPoint, WifiConfigUiBase.MODE_CONNECT);
-        dialog.show();
+        mDialog.show();
-        dialog.setOnDismissListener(this);
+        mDialog.setOnDismissListener(this);
     }
 
     @Override
@@ -79,6 +81,15 @@ public class WifiDialogActivity extends Activity implements WifiDialog.WifiDialo
         overridePendingTransition(0, 0);
     }
 
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        if (mDialog != null && mDialog.isShowing()) {
+            mDialog.dismiss();
+            mDialog = null;
+        }
+    }
+
     @Override
     public void onForget(WifiDialog dialog) {
         final WifiManager wifiManager = getSystemService(WifiManager.class);
@@ -147,6 +158,7 @@ public class WifiDialogActivity extends Activity implements WifiDialog.WifiDialo
 
     @Override
     public void onDismiss(DialogInterface dialogInterface) {
+        mDialog = null;
         finish();
     }
 }