Add Wifi Setup screen for Setup Wizard with XL size screen.

* Add WifiSettingsForSetupWizardXL as a new Activity
The activity has WifiSettings fragment in it. It also contains
several buttons, texts around the fragment.

* Making configuration UI part of Preference list.
In Wifi Setup for Setup Wizard XL, WifiSettings fragment lets
a UI for configuring access points shown inside a
PregerenceCategory object, while it has been shown as Dialog.

To achieve this action, WifiDialog is decomposed into two parts:
- WifiConfigUiBase (Mainly UI part)
- WifiConfigController (Mainly Wifi controller part)

All codes for wifi configuration in WifiDialog is now in
WifiConfigController, which is reused from
WifiConfigPreference.

* Misc stuff
- Remove AccessPoint#compareTo(). Instead,
  AccessPoint.AccessPointComparater should be used when needed.

Change-Id: I520d690d3301837d32f91dad54a973a379ce1989
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 2885390..8cb1ec3 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -99,6 +99,11 @@
             </intent-filter>
         </activity-alias>
 
+        <activity android:name=".wifi.WifiSettingsForSetupWizardXL"
+                  android:clearTaskOnLaunch="true"
+                  android:screenOrientation="landscape"
+                  android:exported="true" />
+
         <activity android:name=".wifi.AdvancedSettings"
                 android:label="@string/wifi_ip_settings_titlebar"
                 >