Address review comments for group member list

briar-android/AndroidManifest.xml

@@ -133,7 +133,7 @@
 
 			<activity
 			android:name=".android.privategroup.memberlist.GroupMemberListActivity"
-			android:label="@string/app_name"
+			android:label="@string/groups_member_list"
 			android:parentActivityName=".android.privategroup.conversation.GroupActivity"
 			android:windowSoftInputMode="adjustResize|stateHidden">
 			<meta-data

briar-android/src/org/briarproject/android/privategroup/conversation/GroupActivity.java

@@ -140,7 +140,6 @@ public class GroupActivity extends
 			case R.id.action_group_member_list:
 				Intent i = new Intent(this, GroupMemberListActivity.class);
 				i.putExtra(GROUP_ID, groupId.getBytes());
-				i.putExtra(GROUP_NAME, getTitle());
 				ActivityOptionsCompat options =
 						makeCustomAnimation(this, android.R.anim.slide_in_left,
 								android.R.anim.slide_out_right);

briar-android/src/org/briarproject/android/privategroup/memberlist/GroupMemberListActivity.java

@@ -41,9 +41,6 @@ public class GroupMemberListActivity extends BriarActivity {
 		byte[] b = i.getByteArrayExtra(GROUP_ID);
 		if (b == null) throw new IllegalStateException("No GroupId in intent.");
 		groupId = new GroupId(b);
-		String name = i.getStringExtra(GROUP_NAME);
-		if (name == null) throw new IllegalStateException("No name in intent.");
-		setTitle(name + " " + getString(R.string.groups_member_list));
 
 		list = (BriarRecyclerView) findViewById(R.id.list);
 		LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);

briar-android/src/org/briarproject/android/privategroup/memberlist/MemberListItem.java

@@ -5,15 +5,15 @@ import org.briarproject.api.identity.Author.Status;
 import org.briarproject.api.nullsafety.NotNullByDefault;
 import org.briarproject.api.privategroup.GroupMember;
 
-import javax.annotation.concurrent.NotThreadSafe;
+import javax.annotation.concurrent.Immutable;
 
-@NotThreadSafe
+@Immutable
 @NotNullByDefault
-public class MemberListItem {
+class MemberListItem {
 
 	private final Author member;
-	private Status status;
-	private boolean sharing;
+	private final Status status;
+	private final boolean sharing;
 
 	public MemberListItem(GroupMember groupMember) {
 		this.member = groupMember.getAuthor();