[Andorid] ClipDrawable progress bar experiment.

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"
@@ skipping 42 matching lines @@
                 android:scaleType="center"
                 android:contentDescription="@null"/>
             <org.chromium.chrome.browser.widget.TintedImageButton
                 android:id="@+id/menu_button"
                 android:layout_width="38dp"
                 android:layout_height="38dp"
                 android:src="@drawable/btn_menu"
                 android:background="?attr/selectableItemBackground"
                 android:scaleType="center"/>
         </LinearLayout>
-        <org.chromium.chrome.browser.widget.ToolbarProgressBar
+        <org.chromium.chrome.browser.widget.ClipDrawableProgressBar
             android:id="@+id/progress"
-            style="@android:style/Widget.Holo.Light.ProgressBar.Horizontal"
-            android:progressDrawable="@drawable/progress_bar"
             android:layout_width="match_parent"
             android:layout_height="2dp"
-            android:progress="0" />
+            android:src="@drawable/clip_drawable_progress_bar" />
     </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>