Move SummaryForAllUidLoader to SettingsLib.

In order to show the data usage per app on Android Wear,
I'm moving SummaryForAllUidLoader to SettingsLib so that
the code can be reused.

Change-Id: I1833492d4a3b513405bfc1069b8656d04dd37c48
diff --git a/src/com/android/settings/DataUsageSummary.java b/src/com/android/settings/DataUsageSummary.java
index 5c1a94d..1bb2a51 100644
--- a/src/com/android/settings/DataUsageSummary.java
+++ b/src/com/android/settings/DataUsageSummary.java
@@ -129,7 +129,6 @@
 import com.android.internal.telephony.PhoneConstants;
 import com.android.settings.drawable.InsetBoundsDrawable;
 import com.android.settings.net.DataUsageMeteredSettings;
-import com.android.settings.net.SummaryForAllUidLoader;
 import com.android.settings.net.UidDetail;
 import com.android.settings.net.UidDetailProvider;
 import com.android.settings.search.BaseSearchIndexProvider;
@@ -142,6 +141,7 @@
 import com.android.settingslib.NetworkPolicyEditor;
 import com.android.settingslib.net.ChartData;
 import com.android.settingslib.net.ChartDataLoader;
+import com.android.settingslib.net.SummaryForAllUidLoader;
 import com.google.android.collect.Lists;
 
 import libcore.util.Objects;