Adding option for adding new tab in tab manager for chrome shell.

chrome/android/shell/res/layout/chrome_shell_activity.xml

 <?xml version="1.0" encoding="utf-8"?>
 
 <!-- Copyright 2014 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.
  -->
 
 <org.chromium.chrome.shell.TabManager android:id="@+id/tab_manager"
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical">
     <org.chromium.chrome.shell.ChromeShellToolbar android:id="@+id/toolbar"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:orientation="horizontal"
         android:background="@drawable/progress">
         <org.chromium.chrome.browser.widget.TintedImageButton
+            android:id="@+id/add_button"
+            android:layout_width="38dp"
+            android:layout_height="38dp"
+            android:src="@android:drawable/ic_menu_add"
+             android:visibility="gone"

[Bernhard Bauer, 2014/11/11 11:34:02]

One less space.

[divya.bansal, 2014/11/12 06:45:48]

Done.

+            android:scaleType="center"/>
+        <org.chromium.chrome.browser.widget.TintedImageButton
             android:id="@+id/stop_reload_button"
             android:layout_width="38dp"
             android:layout_height="38dp"
             android:src="@drawable/btn_toolbar_stop"
             android:background="?android:attr/selectableItemBackground"
             android:scaleType="center"/>
         <EditText android:id="@+id/url"
             android:layout_width="0dp"
             android:layout_height="wrap_content"
             android:layout_weight="1"
@@ skipping 22 matching lines @@
             android:background="?android:attr/selectableItemBackground"
             android:scaleType="center"/>
     </org.chromium.chrome.shell.ChromeShellToolbar>
     <FrameLayout android:id="@+id/content_container"
         android:layout_width="match_parent"
         android:layout_height="0dp"
         android:layout_weight="1">
     </FrameLayout>
 
 </org.chromium.chrome.shell.TabManager>