Lock the orientation for FallbackHome

Set FallbackHome's orientation to nosensor in the manifest, so it
will always be shown in the natural device orientation.

Bug: 30040032
Change-Id: I875fa6d112db23273026dbc39b5d32748d7e99f1

AndroidManifest.xml

@@ -2362,6 +2362,7 @@
         <!-- Triggered when user-selected home app isn't encryption aware -->
         <activity android:name=".FallbackHome"
                   android:excludeFromRecents="true"
+                  android:screenOrientation="nosensor"
                   android:theme="@style/FallbackHome">
             <intent-filter android:priority="-1000">
                 <action android:name="android.intent.action.MAIN" />