Update UI for Wifi Direct settings

- Change the launching preference from using an intent to directly a
fragemnt
- Partially convert WifiP2pSettings to a DashboardFragment
- Add a controller to control each pref category, when they have no
child, hide.
- Add a controller to control device's own AP name.

Change-Id: I23685c4d4a85f80ceab5a576005e693e6f8b7cc4
Fix: 36859626
Test: make RunSettingsRoboTests
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 09ee424..2bb81a1 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -268,7 +268,7 @@
 
         <activity android:name="Settings$ConfigureWifiSettingsActivity"
                 android:taskAffinity="com.android.settings"
-                android:label="@string/wifi_configure_titlebar"
+                android:label="@string/wifi_configure_settings_preference_title"
                 android:icon="@drawable/ic_settings_wireless"
                 android:configChanges="orientation|keyboardHidden|screenSize"
                 android:parentActivityName="Settings$WifiSettingsActivity">