Docsui-level work for implementing Eject on Roots list.

1. Added Eject Icon for Roots that support eject
2. Added Context Menu for RootsFragment (Settings and Eject)

Bug: 29584653
Change-Id: I97f582de05763e3f0327bc0d2dc6d4e2222e047c
diff --git a/res/menu/root_context_menu.xml b/res/menu/root_context_menu.xml
new file mode 100644
index 0000000..0cf00a4
--- /dev/null
+++ b/res/menu/root_context_menu.xml
@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2016 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<menu xmlns:android="http://schemas.android.com/apk/res/android">
+    <item
+        android:id="@+id/menu_eject_root"
+        android:title="@string/menu_eject_root" />
+    <item
+        android:id="@+id/menu_settings"
+        android:title="@string/menu_settings" />
+</menu>