Make LinearColorBar support RTL

- Move the class to widget package
- Remove a bunch of useless drawing

Change-Id: I82f840819c89eaf3cf9b7a87e56f1031989e3262
Fixes: 62700884
Test:  robotest

src/com/android/settings/datausage/DataUsageSummary.java

@@ -20,8 +20,6 @@ import android.content.Context;
 import android.content.Intent;
 import android.net.NetworkPolicyManager;
 import android.net.NetworkTemplate;
-import android.net.wifi.WifiConfiguration;
-import android.net.wifi.WifiManager;
 import android.os.Bundle;
 import android.os.UserManager;
 import android.provider.SearchIndexableResource;