Persist the user's active audio device choice across chromeos session and reboots.

extensions/browser/api/audio/audio_apitest.cc

 // Copyright (c) 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 <stddef.h>
 #include <stdint.h>
 
 #include "base/message_loop/message_loop.h"
 #include "build/build_config.h"
 #include "extensions/shell/test/shell_apitest.h"
@@ skipping 191 matching lines @@
 }
 
 IN_PROC_BROWSER_TEST_F(AudioApiTest, OnInputMuteChanged) {
   AudioNodeList audio_nodes;
   audio_nodes.push_back(kJabraMic1);
   audio_nodes.push_back(kUSBCameraMic);
   SetUpCrasAudioHandlerWithTestingNodes(audio_nodes);
 
   // Set the jabra mic to be the active input device.
   AudioDevice jabra_mic(kJabraMic1);
-  cras_audio_handler_->SwitchToDevice(jabra_mic, true);
+  cras_audio_handler_->SwitchToDevice(
+      jabra_mic, true, chromeos::CrasAudioHandler::ACTIVATE_BY_USER);
   EXPECT_EQ(kJabraMic1.id, cras_audio_handler_->GetPrimaryActiveInputNode());
 
   // Un-mute the input.
   cras_audio_handler_->SetInputMute(false);
   EXPECT_FALSE(cras_audio_handler_->IsInputMuted());
 
   // Loads background app.
   ExtensionTestMessageListener load_listener("loaded", false);
   ExtensionTestMessageListener result_listener("success", false);
   result_listener.set_failure_message("failure");
@@ skipping 67 matching lines @@
 
   // Verify the background app got the onNodesChanged event
   // with the last node removed.
   ASSERT_TRUE(result_listener.WaitUntilSatisfied());
   EXPECT_EQ("success", result_listener.message());
 }
 
 #endif  // OS_CHROMEOS
 
 }  // namespace extensions