Data usage app labels, protect system, hide empty.

Derive better labels from PackageManager, including for sharedUid
case.  Disable "App settings" button when no ResolveInfo found, and
hide "Restrict" checkbox for system UIDs.  Also hide apps with 0
bytes usage.

Change-Id: I4b0a66f6912c02c56bfcbcb5b46f3ae2ba0df504

src/com/android/settings/widget/ChartNetworkSeriesView.java

@@ -157,7 +157,8 @@ public class ChartNetworkSeriesView extends View {
         if (LOGD) {
             final RectF bounds = new RectF();
             mPathFill.computeBounds(bounds, true);
-            Log.d(TAG, "onLayout() rendered with bounds=" + bounds.toString());
+            Log.d(TAG, "onLayout() rendered with bounds=" + bounds.toString() + " and totalData="
+                    + totalData);
         }
 
         // drop to bottom of graph from current location