Make AudioRendererMixerInput::SwitchOutputDevice to work correctly even if it has not been initiali…

media/base/audio_renderer_mixer_input.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 "media/base/audio_renderer_mixer_input.h"
 
 #include <cmath>
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
@@ skipping 109 matching lines @@
 
 void AudioRendererMixerInput::SwitchOutputDevice(
     const std::string& device_id,
     const url::Origin& security_origin,
     const OutputDeviceStatusCB& callback) {
   if (device_id == device_id_) {
     callback.Run(OUTPUT_DEVICE_STATUS_OK);
     return;
   }
 
-  OutputDeviceStatus new_mixer_status = OUTPUT_DEVICE_STATUS_ERROR_INTERNAL;
-  AudioRendererMixer* new_mixer =
-      mixer_pool_->GetMixer(owner_id_, params_, latency_, device_id,
-                            security_origin, &new_mixer_status);
-  if (new_mixer_status != OUTPUT_DEVICE_STATUS_OK) {
-    callback.Run(new_mixer_status);
-    return;
-  }
+  if (mixer_) {
+    OutputDeviceStatus new_mixer_status = OUTPUT_DEVICE_STATUS_ERROR_INTERNAL;
+    AudioRendererMixer* new_mixer =
+        mixer_pool_->GetMixer(owner_id_, params_, latency_, device_id,
+                              security_origin, &new_mixer_status);
+    if (new_mixer_status != OUTPUT_DEVICE_STATUS_OK) {
+      callback.Run(new_mixer_status);
+      return;
+    }
 
-  device_id_ = device_id;
-  security_origin_ = security_origin;
-
-  if (mixer_) {
     bool was_playing = playing_;
     Stop();
+    device_id_ = device_id;
+    security_origin_ = security_origin;
     mixer_ = new_mixer;
     mixer_->AddErrorCallback(error_cb_);
     started_ = true;
+
     if (was_playing)
       Play();
+
   } else {
-    mixer_pool_->ReturnMixer(new_mixer);
+    OutputDeviceStatus new_mixer_status =
+        mixer_pool_
+            ->GetOutputDeviceInfo(owner_id_, 0 /* session_id */, device_id,
+                                  security_origin)
+            .device_status();
+    if (new_mixer_status != OUTPUT_DEVICE_STATUS_OK) {
+      callback.Run(new_mixer_status);
+      return;
+    }
+    device_id_ = device_id;
+    security_origin_ = security_origin;
   }
 
   callback.Run(OUTPUT_DEVICE_STATUS_OK);
 }
 
 double AudioRendererMixerInput::ProvideInput(AudioBus* audio_bus,
                                              uint32_t frames_delayed) {
   TRACE_EVENT0("audio", "AudioRendererMixerInput::ProvideInput");
   int frames_filled = callback_->Render(audio_bus, frames_delayed, 0);
 
@@ skipping 10 matching lines @@
     base::AutoLock auto_lock(volume_lock_);
     return frames_filled > 0 ? volume_ : 0;
   }
 }
 
 void AudioRendererMixerInput::OnRenderError() {
   callback_->OnRenderError();
 }
 
 }  // namespace media