Last_n: do not save snapshot of custom tabs.

chrome/browser/android/offline_pages/offline_page_utils.cc

Index: chrome/browser/android/offline_pages/offline_page_utils.cc
diff --git a/chrome/browser/android/offline_pages/offline_page_utils.cc b/chrome/browser/android/offline_pages/offline_page_utils.cc
index 1d304f2adb0ca37b64d3f7fa7d2b808abcfaf607..b56f8cb63e87ea9c7fac2cbd5950aeff106ca2b4 100644
--- a/chrome/browser/android/offline_pages/offline_page_utils.cc
+++ b/chrome/browser/android/offline_pages/offline_page_utils.cc
@@ -158,6 +158,14 @@ bool OfflinePageUtils::GetTabId(content::WebContents* web_contents,
 }
 
 // static
+bool OfflinePageUtils::IsCurrentlyACustomTab(
+    content::WebContents* web_contents) {
+  TabAndroid* tab_android = TabAndroid::FromWebContents(web_contents);
+  DCHECK(tab_android);
+  return tab_android && tab_android->IsCurrentlyACustomTab();
+}
+
+// static
 void OfflinePageUtils::CheckExistenceOfPagesWithURL(
     content::BrowserContext* browser_context,
     const std::string name_space,