Remove sdcard developer option, avoid data crash.

Remove READ_EXTERNAL_STORAGE enforcement UI, since the permission is
now always enforced.  Check to see if bandwidth module is enabled
when launching data usage, and finish gracefully if disabled.

Bug: 10116515, 10392597
Change-Id: Id0295c405b780a53867934b3bcd0a5f56db7d87a

src/com/android/settings/DataUsageSummary.java

@@ -141,13 +141,13 @@ import com.android.settings.widget.ChartDataUsageView.DataUsageChartListener;
 import com.android.settings.widget.PieChartView;
 import com.google.android.collect.Lists;
 
+import libcore.util.Objects;
+
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.Locale;
 
-import libcore.util.Objects;
-
 /**
  * Panel showing data usage history across various networks, including options
  * to inspect based on usage cycle and control through {@link NetworkPolicy}.
@@ -276,6 +276,16 @@ public class DataUsageSummary extends Fragment {
         mPolicyEditor = new NetworkPolicyEditor(mPolicyManager);
         mPolicyEditor.read();
 
+        try {
+            if (!mNetworkService.isBandwidthControlEnabled()) {
+                Log.w(TAG, "No bandwidth control; leaving");
+                getActivity().finish();
+            }
+        } catch (RemoteException e) {
+            Log.w(TAG, "No bandwidth control; leaving");
+            getActivity().finish();
+        }
+
         try {
             mStatsSession = mStatsService.openSession();
         } catch (RemoteException e) {