Do not submit: high level overview patch.

chrome/browser/android/tab_android.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_BROWSER_ANDROID_TAB_ANDROID_H_
 #define CHROME_BROWSER_ANDROID_TAB_ANDROID_H_
 
 #include <jni.h>
 
 #include "base/android/jni_helper.h"
 #include "base/callback_forward.h"
 #include "base/string16.h"
+#include "chrome/browser/sessions/session_id.h"
 #include "chrome/browser/ui/toolbar/toolbar_model.h"
 
 class GURL;
 class SkBitmap;
 
 namespace browser_sync {
 class SyncedTabDelegate;
 }
 
 namespace content {
 struct ContextMenuParams;
 class WebContents;
 }
 
 class TabAndroid {
  public:
   TabAndroid(JNIEnv* env, jobject obj);
 
   // Convenience method to retrieve the Tab associated with the passed
   // WebContents.  Can return NULL.
   static TabAndroid* FromWebContents(content::WebContents* web_contents);
 
   static TabAndroid* GetNativeTab(JNIEnv* env, jobject obj);
 
   // TODO(tedchoc): Make pure virtual once all derived classes can be updated.
   virtual content::WebContents* GetWebContents();
 
   virtual browser_sync::SyncedTabDelegate* GetSyncedTabDelegate() = 0;
 
+  virtual int64 GetSyncSessionId() = 0;
+  virtual void SetSyncSessionId(int64 sync_id) = 0;
+
   virtual ToolbarModel::SecurityLevel GetSecurityLevel();
 
-  int id() const {
-    return tab_id_;
-  }
+  const SessionID& id() const { return tab_id_; }
 
   virtual void OnReceivedHttpAuthRequest(jobject auth_handler,
                                          const string16& host,
                                          const string16& realm) = 0;
 
   // Called to show the regular context menu that is triggered by a long press.
   virtual void ShowContextMenu(const content::ContextMenuParams& params) = 0;
 
   // Called to show a custom context menu. Used by the NTP.
   virtual void ShowCustomContextMenu(
@@ skipping 17 matching lines @@
 
   static bool RegisterTabAndroid(JNIEnv* env);
  protected:
   virtual ~TabAndroid();
 
   static void InitTabHelpers(content::WebContents* web_contents);
 
   static content::WebContents* InitWebContentsFromView(JNIEnv* env,
                                                        jobject content_view);
 
-  int tab_id_;
+  SessionID tab_id_;
 
  private:
   JavaObjectWeakGlobalRef weak_java_tab_;
 };
 
 #endif  // CHROME_BROWSER_ANDROID_TAB_ANDROID_H_