Make TetherSettings use the new tether api.

The new API handles all the provisioning logic so this area can
get significant code cleanup.

Change-Id: I4bcffb14b3ce26a01d17ec149599d63b0b4392f1
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index ddf551e..e02f69b 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -455,7 +455,7 @@
         <activity android:name="TetherProvisioningActivity"
             android:exported="true"
             android:permission="android.permission.TETHER_PRIVILEGED"
-            android:theme="@android:style/Theme.Translucent.NoTitleBar">
+            android:theme="@style/Theme.ProvisioningActivity">
             <intent-filter android:priority="1">
                 <action android:name="android.settings.TETHER_PROVISIONING_UI" />
                 <category android:name="android.intent.category.DEFAULT" />