persist media device id salt across sessions

brightray/browser/browser_context.cc

@@ -4,6 +4,7 @@
 
 #include "browser/browser_context.h"
 
+#include "browser/media/media_device_id_salt.h"
 #include "browser/brightray_paths.h"
 #include "browser/browser_client.h"
 #include "browser/inspectable_web_contents_impl.h"
@@ -56,6 +57,13 @@ class BrowserContext::ResourceContext : public content::ResourceContext {
     return getter_->GetURLRequestContext();
   }
 
+  std::string GetMediaDeviceIDSalt() override {
+    auto media_device_id_salt_ = getter_->GetMediaDeviceIDSalt();
+    if (media_device_id_salt_)
+      return media_device_id_salt_->GetSalt();
+    return content::ResourceContext::GetMediaDeviceIDSalt();
+  }
+
   URLRequestContextGetter* getter_;
 };
 
@@ -114,6 +122,7 @@ void BrowserContext::InitPrefs() {
 
 void BrowserContext::RegisterInternalPrefs(PrefRegistrySimple* registry) {
   InspectableWebContentsImpl::RegisterPrefs(registry);
+  MediaDeviceIDSalt::RegisterPrefs(registry);
 }
 
 URLRequestContextGetter* BrowserContext::GetRequestContext() {
@@ -143,6 +152,14 @@ net::NetworkDelegate* BrowserContext::CreateNetworkDelegate() {
   return new NetworkDelegate;
 }
 
+MediaDeviceIDSalt* BrowserContext::GetMediaDeviceIDSalt() {
+  if (IsOffTheRecord())
+    return nullptr;
+  if (!media_device_id_salt_.get())
+    media_device_id_salt_.reset(new MediaDeviceIDSalt(prefs_.get()));
+  return media_device_id_salt_.get();
+}
+
 base::FilePath BrowserContext::GetPath() const {
   return path_;
 }

brightray/browser/browser_context.h

@@ -24,6 +24,7 @@ class SpecialStoragePolicy;
 
 namespace brightray {
 
+class MediaDeviceIDSalt;
 class PermissionManager;
 
 class BrowserContext : public base::RefCounted<BrowserContext>,
@@ -87,6 +88,7 @@ class BrowserContext : public base::RefCounted<BrowserContext>,
 
   // URLRequestContextGetter::Delegate:
   net::NetworkDelegate* CreateNetworkDelegate() override;
+  MediaDeviceIDSalt* GetMediaDeviceIDSalt() override;
 
   base::FilePath GetPath() const override;
 
@@ -128,6 +130,7 @@ class BrowserContext : public base::RefCounted<BrowserContext>,
   scoped_refptr<storage::SpecialStoragePolicy> storage_policy_;
   std::unique_ptr<PrefService> prefs_;
   std::unique_ptr<PermissionManager> permission_manager_;
+  std::unique_ptr<MediaDeviceIDSalt> media_device_id_salt_;
 
   base::WeakPtrFactory<BrowserContext> weak_factory_;
 

brightray/browser/media/media_device_id_salt.cc

@@ -0,0 +1,53 @@
+// 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.
+#include "browser/media/media_device_id_salt.h"
+
+#include "components/prefs/pref_registry_simple.h"
+#include "components/prefs/pref_service.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/resource_context.h"
+
+using content::BrowserThread;
+
+namespace brightray {
+
+namespace {
+
+const char kMediaDeviceIdSalt[] = "brightray.media.device_id_salt";
+
+}  // namespace
+
+MediaDeviceIDSalt::MediaDeviceIDSalt(PrefService* pref_service) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  media_device_id_salt_.Init(kMediaDeviceIdSalt, pref_service);
+  if (media_device_id_salt_.GetValue().empty()) {
+    media_device_id_salt_.SetValue(
+        content::ResourceContext::CreateRandomMediaDeviceIDSalt());
+  }
+}
+
+MediaDeviceIDSalt::~MediaDeviceIDSalt() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  media_device_id_salt_.Destroy();
+}
+
+std::string MediaDeviceIDSalt::GetSalt() {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  return media_device_id_salt_.GetValue();
+}
+
+// static
+void MediaDeviceIDSalt::RegisterPrefs(PrefRegistrySimple* registry) {
+  registry->RegisterStringPref(kMediaDeviceIdSalt, std::string());
+}
+
+// static
+void MediaDeviceIDSalt::Reset(PrefService* pref_service) {
+  pref_service->SetString(
+      kMediaDeviceIdSalt,
+      content::ResourceContext::CreateRandomMediaDeviceIDSalt());
+}
+
+}  // namespace brightray

brightray/browser/media/media_device_id_salt.h

@@ -0,0 +1,40 @@
+// 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 BRIGHTRAY_BROWSER_MEDIA_MEDIA_DEVICE_ID_SALT_H_
+#define BRIGHTRAY_BROWSER_MEDIA_MEDIA_DEVICE_ID_SALT_H_
+
+#include <string>
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "components/prefs/pref_member.h"
+
+class PrefRegistrySimple;
+class PrefService;
+
+namespace brightray {
+
+// MediaDeviceIDSalt is responsible for creating and retrieving a salt string
+// that is used for creating MediaSource IDs that can be cached by a web
+// service. If the cache is cleared, the  MediaSourceIds are invalidated.
+class MediaDeviceIDSalt {
+ public:
+  explicit MediaDeviceIDSalt(PrefService* pref_service);
+  ~MediaDeviceIDSalt();
+
+  std::string GetSalt();
+
+  static void RegisterPrefs(PrefRegistrySimple* pref_registry);
+  static void Reset(PrefService* pref_service);
+
+ private:
+  StringPrefMember media_device_id_salt_;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaDeviceIDSalt);
+};
+
+}  // namespace brightray
+
+#endif  // BRIGHTRAY_BROWSER_MEDIA_MEDIA_DEVICE_ID_SALT_H_

brightray/browser/url_request_context_getter.h

@@ -31,6 +31,7 @@ class URLRequestJobFactory;
 namespace brightray {
 
 class DevToolsNetworkControllerHandle;
+class MediaDeviceIDSalt;
 class NetLog;
 
 class URLRequestContextGetter : public net::URLRequestContextGetter {
@@ -57,6 +58,7 @@ class URLRequestContextGetter : public net::URLRequestContextGetter {
     GetRequireCTDelegate() {
       return nullptr;
     }
+    virtual MediaDeviceIDSalt* GetMediaDeviceIDSalt() { return nullptr; }
   };
 
   URLRequestContextGetter(
@@ -77,6 +79,9 @@ class URLRequestContextGetter : public net::URLRequestContextGetter {
 
   net::HostResolver* host_resolver();
   net::URLRequestJobFactory* job_factory() const { return job_factory_; }
+  MediaDeviceIDSalt* GetMediaDeviceIDSalt() const {
+    return delegate_->GetMediaDeviceIDSalt();
+  }
 
  private:
   Delegate* delegate_;

brightray/filenames.gypi

@@ -43,6 +43,8 @@
       'browser/mac/notification_presenter_mac.mm',
       'browser/media/media_capture_devices_dispatcher.cc',
       'browser/media/media_capture_devices_dispatcher.h',
+      'browser/media/media_device_id_salt.cc',
+      'browser/media/media_device_id_salt.h',
       'browser/media/media_stream_devices_controller.cc',
       'browser/media/media_stream_devices_controller.h',
       'browser/net/devtools_network_conditions.cc',