Fix classes that have too many virtuals for inline constructors.

content/browser/service_worker/service_worker_version.h

 // Copyright 2013 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 CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_VERSION_H_
 #define CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_VERSION_H_
 
 #include <map>
 #include <queue>
 #include <set>
@@ skipping 106 matching lines @@
     virtual void OnControlleeAdded(ServiceWorkerVersion* version,
                                    ServiceWorkerProviderHost* provider_host) {}
     virtual void OnControlleeRemoved(ServiceWorkerVersion* version,
                                      ServiceWorkerProviderHost* provider_host) {
     }
     // Fires when a version transitions from having a controllee to not.
     virtual void OnNoControllees(ServiceWorkerVersion* version) {}
     virtual void OnCachedMetadataUpdated(ServiceWorkerVersion* version) {}
 
    protected:
+    Listener() = default;
     virtual ~Listener() {}
   };
 
   ServiceWorkerVersion(
       ServiceWorkerRegistration* registration,
       const GURL& script_url,
       int64 version_id,
       base::WeakPtr<ServiceWorkerContextCore> context);
 
   int64 version_id() const { return version_id_; }
@@ skipping 521 matching lines @@
   const bool should_exclude_from_uma_ = false;
 
   base::WeakPtrFactory<ServiceWorkerVersion> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerVersion);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_VERSION_H_