Data usage app icons and details, chart labels.

Add app icons into both summary list and details pane. Also show list
of all applications merged under a UID. Draw dates on chart axis, and
avoid flashing policy sweeps when switching networks in detail mode.

Bug: 5087283, 5038812
Change-Id: I1dcd03ca85b517f8726452af8a46b4be9b3d20f1

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

@@ -29,7 +29,6 @@ import android.text.Layout.Alignment;
 import android.text.SpannableStringBuilder;
 import android.text.TextPaint;
 import android.util.AttributeSet;
-import android.util.Log;
 import android.util.MathUtils;
 import android.view.MotionEvent;
 import android.view.View;