Turn webspeech on/off when tab goes fore/background

chrome/browser/media/media_stream_devices_controller.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_devices_controller.h"
 
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "base/prefs/pref_service.h"
 #include "base/prefs/scoped_user_pref_update.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/content_settings/content_settings_provider.h"
 #include "chrome/browser/content_settings/host_content_settings_map.h"
 #include "chrome/browser/content_settings/tab_specific_content_settings.h"
 #include "chrome/browser/media/media_capture_devices_dispatcher.h"
 #include "chrome/browser/media/media_stream_capture_indicator.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/content_settings.h"
 #include "chrome/common/content_settings_pattern.h"
 #include "chrome/common/pref_names.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "content/public/browser/browser_thread.h"
+#include "content/public/browser/render_widget_host_view.h"
 #include "content/public/common/media_stream_request.h"
 #include "extensions/common/constants.h"
 #include "grit/generated_resources.h"
 #include "grit/theme_resources.h"
 #include "ui/base/l10n/l10n_util.h"
-

[DaleCurtis, 2014/07/23 22:17:19]

Line break is normally kept here.

[qinmin, 2014/07/23 22:28:48]

Done.

 #if defined(OS_CHROMEOS)
 #include "chrome/browser/chromeos/login/users/user_manager.h"
 #endif
 
 using content::BrowserThread;
 
 namespace {
 
 bool HasAvailableDevicesForRequest(const content::MediaStreamRequest& request) {
   const content::MediaStreamDevices* audio_devices =
@@ skipping 609 matching lines @@
   }
   if (IsDeviceVideoCaptureRequestedAndAllowed()) {
     request_permissions_[content::MEDIA_DEVICE_VIDEO_CAPTURE].permission =
         MEDIA_BLOCKED_BY_USER;
   }
 
   content_settings_->OnMediaStreamPermissionSet(request_.security_origin,
                                                 request_permissions_);
 }
 
 bool MediaStreamDevicesController::IsDeviceAudioCaptureRequestedAndAllowed()

[DaleCurtis, 2014/07/23 22:17:19]

Presumably all three of these methods are being called on the UI thread only?

[qinmin, 2014/07/23 22:28:48]

Yes.

On 2014/07/23 22:17:19, DaleCurtis wrote:

     const {
   MediaStreamTypeSettingsMap::const_iterator it =
       request_permissions_.find(content::MEDIA_DEVICE_AUDIO_CAPTURE);
-  return (it != request_permissions_.end() &&
+  return (it != request_permissions_.end() && IsCaptureDeviceRequestAllowed() &&
           it->second.permission == MEDIA_ALLOWED);
 }
 
 bool MediaStreamDevicesController::IsDeviceVideoCaptureRequestedAndAllowed()
     const {
   MediaStreamTypeSettingsMap::const_iterator it =
       request_permissions_.find(content::MEDIA_DEVICE_VIDEO_CAPTURE);
-  return (it != request_permissions_.end() &&
+  return (it != request_permissions_.end() && IsCaptureDeviceRequestAllowed() &&
           it->second.permission == MEDIA_ALLOWED);
 }
+
+bool MediaStreamDevicesController::IsCaptureDeviceRequestAllowed() const {
+#if defined(OS_ANDROID)
+  // Don't approve device requests if the tab was hidden.
+  return web_contents_->GetRenderWidgetHostView()->IsShowing();
+#endif
+  return true;
+}