Update action bar style in app header UI.

- Update background color of actionbar
- Remove elevation of actionbar so it appears to be the same entity as
  app header.
- Add a shadow below app header view. We can't set elevation on app
  header unfortunately because that will add shadow all round the view,
  but we only want shadow below it.
- Updated app icon size/text size per to match UI spec.

Change-Id: I63d7fa42b859a008fa662aaf19848cd40529c2ff
Fix: 37207527
Fix: 37079248
Test: visual && make RunSettingsRoboTests

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

@@ -14,6 +14,8 @@
 
 package com.android.settings.datausage;
 
+import static android.net.NetworkPolicyManager.POLICY_REJECT_METERED_BACKGROUND;
+
 import android.app.Activity;
 import android.app.LoaderManager;
 import android.content.Context;
@@ -57,8 +59,6 @@ import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
-import static android.net.NetworkPolicyManager.POLICY_REJECT_METERED_BACKGROUND;
-
 public class AppDataUsage extends DataUsageBase implements Preference.OnPreferenceChangeListener,
         DataSaverBackend.Listener {
 
@@ -362,7 +362,7 @@ public class AppDataUsage extends DataUsageBase implements Preference.OnPreferen
             .setUid(uid)
             .setButtonActions(AppHeaderController.ActionType.ACTION_APP_INFO,
                 AppHeaderController.ActionType.ACTION_NONE)
-            .done(getPrefContext());
+            .done(activity, getPrefContext());
         getPreferenceScreen().addPreference(pref);
     }