Abstract content::SessionStorageNamespace from core TabRestore code

chrome/browser/sessions/chrome_tab_restore_service_client.cc

Index: chrome/browser/sessions/chrome_tab_restore_service_client.cc
diff --git a/chrome/browser/sessions/chrome_tab_restore_service_client.cc b/chrome/browser/sessions/chrome_tab_restore_service_client.cc
index 922dd6420c188625ba79c568a169ff1f52cca330..760236aa6d6e421d44c13f8f852a6284695999e1 100644
--- a/chrome/browser/sessions/chrome_tab_restore_service_client.cc
+++ b/chrome/browser/sessions/chrome_tab_restore_service_client.cc
@@ -8,6 +8,7 @@
 #include "chrome/browser/sessions/session_service.h"
 #include "chrome/browser/sessions/session_service_factory.h"
 #include "chrome/common/url_constants.h"
+#include "components/sessions/content/content_tab_client_data.h"
 #include "content/public/browser/browser_thread.h"
 
 #if defined(ENABLE_EXTENSIONS)
@@ -110,6 +111,12 @@ std::string ChromeTabRestoreServiceClient::GetExtensionAppIDForWebContents(
   return extension_app_id;
 }
 
+scoped_ptr<sessions::TabClientData>
+ChromeTabRestoreServiceClient::GetTabClientDataForWebContents(
+    content::WebContents* web_contents) {
+  return make_scoped_ptr(new sessions::ContentTabClientData(web_contents));
+}
+
 base::SequencedWorkerPool* ChromeTabRestoreServiceClient::GetBlockingPool() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   return content::BrowserThread::GetBlockingPool();