Clean up settings_entity_header layout.

update layout view IDs, and controller variable names to be more
generic.

Fix: 36734470
Bug: 37669238
Test: make RunSettingsRoboTests
Change-Id: Ib80827ae3eae6d01a600068b4a8a44b239c32511

tests/robotests/src/com/android/settings/applications/AppInfoWithHeaderTest.java

@@ -68,12 +68,12 @@ public class AppInfoWithHeaderTest {
 
     @Test
     public void testAppHeaderIsAdded() {
-        final AppHeaderController appHeaderController = new AppHeaderController(
+        final EntityHeaderController entityHeaderController = new EntityHeaderController(
                 ShadowApplication.getInstance().getApplicationContext(),
                 mAppInfoWithHeader,
                 null);
         when(mFactory.applicationFeatureProvider.newAppHeaderController(mAppInfoWithHeader, null))
-                .thenReturn(appHeaderController);
+                .thenReturn(entityHeaderController);
         mAppInfoWithHeader.onActivityCreated(null);
 
         verify(mAppInfoWithHeader.mScreen).addPreference(any(LayoutPreference.class));