Foreground/background network stats pie chart.

Load foreground/background network stats, showing combined in chart
series, and also separated in pie chart.  Padding to match spec,
updated action bar tabs, and limit width for wide devices.  Also
clear UI options for requesting fragments.  Move to action bar
overflow menu instead of custom icon.  Show detail chart data outside
current inspection range.

Bug: 5106163, 5143670, 5163064, 5162671, 5148713, 5129036, 5096626
Change-Id: I548fef209e1f714f70ee6bf7098dbdb881692df4

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

@@ -105,7 +105,7 @@ public class ChartNetworkSeriesView extends View {
 
     public void setChartColor(int stroke, int fill, int fillSecondary) {
         mPaintStroke = new Paint();
-        mPaintStroke.setStrokeWidth(6.0f);
+        mPaintStroke.setStrokeWidth(4.0f * getResources().getDisplayMetrics().density);
         mPaintStroke.setColor(stroke);
         mPaintStroke.setStyle(Style.STROKE);
         mPaintStroke.setAntiAlias(true);
@@ -165,7 +165,10 @@ public class ChartNetworkSeriesView extends View {
         mPathEstimate.reset();
 
         // bail when not enough stats to render
-        if (mStats == null || mStats.size() < 2) return;
+        if (mStats == null || mStats.size() < 2) {
+            invalidate();
+            return;
+        }
 
         final int width = getWidth();
         final int height = getHeight();
@@ -263,6 +266,8 @@ public class ChartNetworkSeriesView extends View {
         }
 
         mMaxEstimate = totalData;
+
+        invalidate();
     }
 
     public void setEndTime(long endTime) {