OfflinePageModel cleanups - improved CanSavePage() and moved static kInvalidOfflineId to impl

components/offline_pages/offline_page_model.cc

 // Copyright 2015 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.
 
 #include "components/offline_pages/offline_page_model.h"
 
 #include "url/gurl.h"
 
 namespace offline_pages {
 
 // static
-bool OfflinePageModel::CanSavePage(const GURL& url) {
-  return url.SchemeIsHTTPOrHTTPS();
+bool OfflinePageModel::CanSaveURL(const GURL& url) {
+  return url.is_valid() && url.SchemeIsHTTPOrHTTPS();
 }
 
 OfflinePageModel::OfflinePageModel() {}
 
 OfflinePageModel::~OfflinePageModel() {}
 
 }  // namespace offline_pages