Adds a basic offline check to InstallableManager.

chrome/browser/installable/installable_logging.h

 // Copyright 2016 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_INSTALLABLE_INSTALLABLE_LOGGING_H_
 #define CHROME_BROWSER_INSTALLABLE_INSTALLABLE_LOGGING_H_
 
 #include <string>
 
 namespace content {
@@ skipping 28 matching lines @@
   ALREADY_INSTALLED,
   INSUFFICIENT_ENGAGEMENT,
   PACKAGE_NAME_OR_START_URL_EMPTY,
   PREVIOUSLY_BLOCKED,
   PREVIOUSLY_IGNORED,
   SHOWING_NATIVE_APP_BANNER,
   SHOWING_WEB_APP_BANNER,
   FAILED_TO_CREATE_BANNER,
   URL_NOT_SUPPORTED_FOR_WEBAPK,
   IN_INCOGNITO,
+  NOT_OFFLINE_CAPABLE,
   MAX_ERROR_CODE,
 };
 
 // Logs a message associated with |code| with a parameter |param| to the
 // devtools console attached to |web_contents|. Does nothing if |web_contents|
 // is nullptr.
 void LogErrorToConsole(content::WebContents* web_contents,
                        InstallableStatusCode code,
                        const std::string& param);
 
 #endif  // CHROME_BROWSER_INSTALLABLE_INSTALLABLE_LOGGING_H_