Correctly restrict UI for WifiSettings in Guest profile.

Makes sure the restricted user does not see Wifi Preferences
or Saved Networks activity. Also fixes a bug where the progress
bar is displayed starting the activity in Guest mode, and does not go
away. LinkablePreference is changed to make sure titles can be
multi-lined.

Bug: 35317523
Bug: 35318292
Test: to be done in b/35324506
Change-Id: I4a07a2ab3a83c3adaf87226969fd6f16e41c9419

src/com/android/settings/wifi/LinkablePreference.java

@@ -55,11 +55,15 @@ public class LinkablePreference extends Preference {
         super.onBindViewHolder(view);
 
         TextView textView = (TextView) view.findViewById(android.R.id.title);
-        if (textView == null || mContentTitle == null || mClickListener == null) {
+        if (textView == null) {
+            return;
+        }
+        textView.setSingleLine(false);
+
+        if (mContentTitle == null || mClickListener == null) {
             return;
         }
 
-        textView.setSingleLine(false);
         StringBuilder contentBuilder = new StringBuilder().append(mContentTitle);
         if (mContentDescription != null) {
             contentBuilder.append("\n\n");