Make default media device ID salts random by default

content/browser/renderer_host/media/audio_renderer_host.h

 // 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.
 //
 // AudioRendererHost serves audio related requests from AudioRenderer which
 // lives inside the render process and provide access to audio hardware.
 //
 // This class is owned by RenderProcessHostImpl, and instantiated on UI
 // thread, but all other operations and method calls happen on IO thread, so we
 // need to be extra careful about the lifetime of this object. AudioManager is a
@@ skipping 68 matching lines @@
 class ResourceContext;
 
 class CONTENT_EXPORT AudioRendererHost : public BrowserMessageFilter {
  public:
   // Called from UI thread from the owner of this object.
   AudioRendererHost(int render_process_id,
                     media::AudioManager* audio_manager,
                     AudioMirroringManager* mirroring_manager,
                     MediaInternals* media_internals,
                     MediaStreamManager* media_stream_manager,
-                    const ResourceContext::SaltCallback& salt_callback);
+                    const std::string& salt);
 
   // Calls |callback| with the list of AudioOutputControllers for this object.
   void GetOutputControllers(
       const RenderProcessHost::GetAudioOutputControllersCallback&
           callback) const;
 
   // BrowserMessageFilter implementation.
   void OnChannelClosing() override;
   void OnDestruct() const override;
   bool OnMessageReceived(const IPC::Message& message) override;
@@ skipping 148 matching lines @@
   MediaStreamManager* media_stream_manager_;
 
   // A map of stream IDs to audio sources.
   AudioEntryMap audio_entries_;
 
   // The number of streams in the playing state. Atomic read safe from any
   // thread, but should only be updated from the IO thread.
   base::AtomicRefCount num_playing_streams_;
 
   // Salt required to translate renderer device IDs to raw device unique IDs
-  ResourceContext::SaltCallback salt_callback_;
+  std::string salt_;
 
   // Map of device authorizations for streams that are not yet created
   // The key is the stream ID, and the value is a pair. The pair's first element
   // is a bool that is true if the authorization process completes successfully.
   // The second element contains the unique ID of the authorized device.
   std::map<int, std::pair<bool, std::string>> authorizations_;
 
   // The maximum number of simultaneous streams during the lifetime of this
   // host. Reported as UMA stat at shutdown.
   size_t max_simultaneous_streams_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererHost);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_RENDERER_HOST_H_