Redesigned and refactored ScopedMTPDeviceMapEntry, MTPDeviceMapService & MTPDeviceDelegate classes.

chrome/browser/media_gallery/media_file_system_registry.cc

 // Copyright (c) 2012 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.
 
 // MediaFileSystemRegistry implementation.
 
 #include "chrome/browser/media_gallery/media_file_system_registry.h"
 
 #include <set>
 #include <vector>
@@ skipping 112 matching lines @@
                                          const FilePath& fs_path,
                                          const std::string& filesystem_id)
     : name(fs_name),
       path(fs_path),
       fsid(filesystem_id) {
 }
 
 MediaFileSystemInfo::MediaFileSystemInfo() {}
 
 #if defined(SUPPORT_MTP_DEVICE_FILESYSTEM)
-
 ScopedMTPDeviceMapEntry::ScopedMTPDeviceMapEntry(
     const FilePath::StringType& device_location,
     const base::Closure& no_references_callback)
     : device_location_(device_location),
-      delegate_(new MTPDeviceDelegateImpl(device_location)),
       no_references_callback_(no_references_callback) {
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       Bind(&MTPDeviceMapService::AddDelegate,
            base::Unretained(MTPDeviceMapService::GetInstance()),
-           device_location_, make_scoped_refptr(delegate_)));
+           device_location_,
+           new MTPDeviceDelegateImpl(device_location_)));
 }
 
 ScopedMTPDeviceMapEntry::~ScopedMTPDeviceMapEntry() {
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       Bind(&MTPDeviceMapService::RemoveDelegate,
            base::Unretained(MTPDeviceMapService::GetInstance()),
            device_location_));
   no_references_callback_.Run();
 }
-
 #endif  // defined(SUPPORT_MTP_DEVICE_FILESYSTEM)
 
 // The main owner of this class is
 // |MediaFileSystemRegistry::extension_hosts_map_|, but a callback may
 // temporarily hold a reference.
 class ExtensionGalleriesHost
     : public base::RefCountedThreadSafe<ExtensionGalleriesHost>,
       public content::NotificationObserver {
  public:
   // |no_references_callback| is called when the last RenderViewHost reference
@@ skipping 505 matching lines @@
   SystemMonitor* system_monitor = SystemMonitor::Get();
   if (system_monitor)
     system_monitor->AddDevicesChangedObserver(this);
 }
 
 MediaFileSystemRegistry::~MediaFileSystemRegistry() {
   // SystemMonitor may be NULL in unit tests.
   SystemMonitor* system_monitor = SystemMonitor::Get();
   if (system_monitor)
     system_monitor->RemoveDevicesChangedObserver(this);
+#if defined(SUPPORT_MTP_DEVICE_FILESYSTEM)
+  DCHECK(mtp_device_delegate_map_.empty());
+#endif
 }
 
 void MediaFileSystemRegistry::OnMediaGalleriesRememberedGalleriesChanged(
     PrefServiceBase* prefs) {
   // Find the Profile that contains the source PrefService.
   PrefChangeRegistrarMap::iterator pref_change_it =
       pref_change_registrar_map_.begin();
   for (; pref_change_it != pref_change_registrar_map_.end(); ++pref_change_it) {
     if (pref_change_it->first->GetPrefs() == prefs)
       break;
@@ skipping 23 matching lines @@
     gallery_host_it->second->RevokeOldGalleries(
         preferences->GalleriesForExtension(*extension));
   }
 }
 
 #if defined(SUPPORT_MTP_DEVICE_FILESYSTEM)
 ScopedMTPDeviceMapEntry*
 MediaFileSystemRegistry::GetOrCreateScopedMTPDeviceMapEntry(
     const FilePath::StringType& device_location) {
   MTPDeviceDelegateMap::iterator delegate_it =
-      mtp_delegate_map_.find(device_location);
-  if (delegate_it != mtp_delegate_map_.end() && delegate_it->second.get())
+      mtp_device_delegate_map_.find(device_location);
+  if (delegate_it != mtp_device_delegate_map_.end())
     return delegate_it->second;
   ScopedMTPDeviceMapEntry* mtp_device_host = new ScopedMTPDeviceMapEntry(
       device_location, base::Bind(
           &MediaFileSystemRegistry::RemoveScopedMTPDeviceMapEntry,
           base::Unretained(this), device_location));
-  mtp_delegate_map_[device_location] = mtp_device_host->AsWeakPtr();
+  mtp_device_delegate_map_[device_location] = mtp_device_host;
   return mtp_device_host;
 }
 
 void MediaFileSystemRegistry::RemoveScopedMTPDeviceMapEntry(
     const FilePath::StringType& device_location) {
   MTPDeviceDelegateMap::iterator delegate_it =
-      mtp_delegate_map_.find(device_location);
-  DCHECK(delegate_it != mtp_delegate_map_.end());
-  mtp_delegate_map_.erase(delegate_it);
+      mtp_device_delegate_map_.find(device_location);
+  DCHECK(delegate_it != mtp_device_delegate_map_.end());
+  mtp_device_delegate_map_.erase(delegate_it);
 }
 #endif
 
 void MediaFileSystemRegistry::OnExtensionGalleriesHostEmpty(
     Profile* profile, const std::string& extension_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   ExtensionGalleriesHostMap::iterator extension_hosts =
       extension_hosts_map_.find(profile);
   DCHECK(extension_hosts != extension_hosts_map_.end());
   ExtensionHostMap::size_type erase_count =
       extension_hosts->second.erase(extension_id);
   DCHECK_EQ(1U, erase_count);
   if (extension_hosts->second.empty()) {
     extension_hosts_map_.erase(extension_hosts);
 
     PrefChangeRegistrarMap::iterator pref_it =
         pref_change_registrar_map_.find(profile);
     DCHECK(pref_it != pref_change_registrar_map_.end());
     delete pref_it->second;
     pref_change_registrar_map_.erase(pref_it);
   }
 }
 
 }  // namespace chrome