Create org.chromium.content_public.common and move two classes there.

chrome/android/shell/java/src/org/chromium/chrome/shell/ChromeShellTab.java

 // 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.
 
 package org.chromium.chrome.shell;
 
 import android.content.Context;
 import android.text.TextUtils;
 
 import org.chromium.chrome.browser.Tab;
 import org.chromium.chrome.browser.UrlUtilities;
 import org.chromium.chrome.browser.contextmenu.ChromeContextMenuPopulator;
 import org.chromium.chrome.browser.contextmenu.ContextMenuPopulator;
 import org.chromium.chrome.browser.infobar.AutoLoginProcessor;
 import org.chromium.content.browser.ContentViewClient;
-import org.chromium.content_public.Referrer;
 import org.chromium.content_public.browser.LoadUrlParams;
 import org.chromium.content_public.browser.NavigationController;
 import org.chromium.content_public.browser.WebContents;
+import org.chromium.content_public.common.Referrer;
 import org.chromium.ui.base.WindowAndroid;
 
 /**
  * ChromeShell's implementation of a tab. This mirrors how Chrome for Android subclasses
  * and extends {@link Tab}.
  */
 public class ChromeShellTab extends Tab {
     // Tab state
     private boolean mIsLoading;
 
@@ skipping 87 matching lines @@
         public void onLoadStarted() {
             mIsLoading = true;
         }
 
         @Override
         public void onLoadStopped() {
             mIsLoading = false;
         }
     }
 }