Remove obsoleted function and add test

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 ac75cfa615373639d1540968f7fa85849c83bffc..2b0b647d0eaa7b87830a5b9cda911e354ede4c77 100644
--- a/chrome/browser/android/offline_pages/offline_page_utils.cc
+++ b/chrome/browser/android/offline_pages/offline_page_utils.cc
@@ -92,18 +92,6 @@ bool OfflinePageUtils::MightBeOfflineURL(const GURL& url) {
 }
 
 // static
-GURL OfflinePageUtils::MaybeGetOfflineURLForOnlineURL(
-    content::BrowserContext* browser_context,
-    const GURL& online_url) {
-  const OfflinePageItem* offline_page =
-      MaybeGetBestOfflinePageForOnlineURL(browser_context, online_url);
-  if (!offline_page)
-    return GURL();
-
-  return offline_page->GetOfflineURL();
-}
-
-// static
 void OfflinePageUtils::GetOfflineURLForOnlineURL(
     content::BrowserContext* browser_context,
     const GURL& online_url,