[Wi-Fi] Support WiFi detail page for OpenRoaming feature in AOSP setting.

Issue: Openroaming should have a specific detail page.
Solution: Apply the mock design to only reserve two preference items:
          1.Auto-connect
          2.Scription details

Bug: 146669261
Test: Add unit test case to test the new controller: WifiSubscriptionDetailPreferenceController2
Change-Id: Iba96500062f412f4cdcd1c8248544657770ab231

src/com/android/settings/wifi/details2/WifiMeteredPreferenceController2.java

@@ -55,7 +55,7 @@ public class WifiMeteredPreferenceController2 extends BasePreferenceController i
 
     @Override
     public int getAvailabilityStatus() {
-        return AVAILABLE;
+        return mWifiEntry.canManageSubscription() ? CONDITIONALLY_UNAVAILABLE : AVAILABLE;
     }
 
     @Override