Resolve the problems where we can leak the system tray UI

chrome/browser/media/media_stream_capture_indicator.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.
 
 #include "chrome/browser/media/media_stream_capture_indicator.h"
 
 #include "base/bind.h"
 #include "base/i18n/rtl.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/app/chrome_command_ids.h"
@@ skipping 196 matching lines @@
 }
 
 void MediaStreamCaptureIndicator::DoDevicesClosedOnUIThread(
     int render_process_id,
     int render_view_id,
     const content::MediaStreamDevices& devices) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   if (!status_icon_)
     return;
 
-  DCHECK(!tabs_.empty());
   RemoveCaptureDeviceTab(render_process_id, render_view_id, devices);
 }
 
 void MediaStreamCaptureIndicator::CreateStatusTray() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   if (status_icon_)
     return;
 
   // If there is no browser process, we should not create the status tray.
   if (!g_browser_process)
@@ skipping 72 matching lines @@
   status_icon_->DisplayBalloon(
       !image.IsEmpty() ? *image.ToImageSkia() :
           *ResourceBundle::GetSharedInstance().GetImageSkiaNamed(
               IDR_APP_DEFAULT_ICON),
       string16(),
       message);
 }
 
 void MediaStreamCaptureIndicator::Hide() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(tabs_.empty());
   if (!status_icon_)
     return;
 
   // If there is no browser process, we should not do anything.
   if (!g_browser_process)
     return;
 
   StatusTray* status_tray = g_browser_process->status_tray();
   if (status_tray != NULL) {
     status_tray->RemoveStatusIcon(status_icon_);
     status_icon_ = NULL;
   }
 }
 
 void MediaStreamCaptureIndicator::UpdateStatusTrayIconContextMenu() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   scoped_ptr<ui::SimpleMenuModel> menu(new ui::SimpleMenuModel(this));
 
   bool audio = false;
   bool video = false;
   int command_id = IDC_MEDIA_CONTEXT_MEDIA_STREAM_CAPTURE_LIST_FIRST;
   for (CaptureDeviceTabs::iterator iter = tabs_.begin();
        iter != tabs_.end();  ++iter) {
     string16 tab_title = GetTitle(iter->render_process_id,
                                   iter->render_view_id);
-    // The tab has gone away.
-    if (tab_title.empty())
+    if (tab_title.empty()) {
+      // Delete the entry since the tab has gone away.
+      tabs_.erase(iter);
       continue;
+    }
 
     // Check if any audio and video devices have been used.
     audio = audio || iter->audio_ref_count > 0;
     video = video || iter->video_ref_count > 0;
 
     string16 message = l10n_util::GetStringFUTF16(
         IDS_MEDIA_STREAM_STATUS_TRAY_MENU_ITEM, tab_title);
     menu->AddItem(command_id, message);
 
     // If reaching the maximum number, no more item will be added to the menu.
     if (command_id == IDC_MEDIA_CONTEXT_MEDIA_STREAM_CAPTURE_LIST_LAST)
       break;
 
     ++command_id;
   }
 
-  // All the tabs have gone away.
-  if (!audio && !video)
+  if (!audio && !video) {
+    Hide();
     return;
+  }
 
   // The icon will take the ownership of the passed context menu.
   status_icon_->SetContextMenu(menu.release());
   UpdateStatusTrayIconDisplay(audio, video);
 }
 
 void MediaStreamCaptureIndicator::UpdateStatusTrayIconDisplay(
     bool audio, bool video) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(audio || video);
@@ skipping 65 matching lines @@
       --iter->video_ref_count;
 
     DCHECK_GE(iter->audio_ref_count, 0);
     DCHECK_GE(iter->video_ref_count, 0);
   }
 
   // Remove the tab if all the devices have been closed.
   if (iter->audio_ref_count == 0 && iter->video_ref_count == 0)
     tabs_.erase(iter);
 
-  if (tabs_.empty())
-    Hide();
-  else
-    UpdateStatusTrayIconContextMenu();
+  UpdateStatusTrayIconContextMenu();
 }