Add a footer at the bottom of the menu for custom tabs

chrome/android/java/res/layout/powered_by_chrome_footer.xml

Index: chrome/android/java/res/layout/powered_by_chrome_footer.xml
diff --git a/chrome/android/java/res/layout/powered_by_chrome_footer.xml b/chrome/android/java/res/layout/powered_by_chrome_footer.xml
new file mode 100644
index 0000000000000000000000000000000000000000..6aeb6bb3a62f405a865a06ba0120b90ebb9b877e
--- /dev/null
+++ b/chrome/android/java/res/layout/powered_by_chrome_footer.xml
@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright 2015 The Chromium Authors. All rights reserved.
+     Use of this source code is governed by a BSD-style license that can be
+     found in the LICENSE file. -->
+
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:background="#f5f5f5" >
+    <View
+        android:layout_width="match_parent"
+        android:layout_height="1dp"
+        android:background="#e0e0e0" />
+    <TextView
+        android:layout_width="match_parent"
+        android:layout_height="@dimen/menu_footer_height"
+        android:paddingTop="1dp"
+        android:paddingStart="16dp"
+        android:paddingEnd="16dp"
+        android:gravity="start|center_vertical"
+        android:textSize="12sp"
+        android:textColor="#616161"
+        android:text="@string/powered_by_chrome_message"
+        android:maxLines="1" />
+</FrameLayout>