Adds method to invoke platform provided audio input UI.

media/audio/win/audio_manager_win.cc

Index: media/audio/win/audio_manager_win.cc
diff --git a/media/audio/win/audio_manager_win.cc b/media/audio/win/audio_manager_win.cc
index 0c896d128eefd9c4bb24cb8ee8c79619687936d5..7b3d6fa91a7dbbdf0e142162d5ba23dc6ff395a6 100644
--- a/media/audio/win/audio_manager_win.cc
+++ b/media/audio/win/audio_manager_win.cc
@@ -11,9 +11,14 @@
 #include <setupapi.h>
 
 #include "base/basictypes.h"
+#include "base/command_line.h"
+#include "base/file_path.h"
+#include "base/path_service.h"
+#include "base/process_util.h"
 #include "base/scoped_ptr.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
+#include "base/win/windows_version.h"
 #include "media/audio/fake_audio_input_stream.h"
 #include "media/audio/fake_audio_output_stream.h"
 #include "media/audio/win/audio_manager_win.h"
@@ -229,6 +234,29 @@ string16 AudioManagerWin::GetAudioInputDeviceModel() {
   return string16();
 }
 
+bool AudioManagerWin::CanShowAudioInputSettings() {
+  return true;
+}
+
+void AudioManagerWin::ShowAudioInputSettings() {
+  std::wstring program;
+  std::string argument;
+  if (base::win::GetVersion() <= base::win::VERSION_XP) {
+    program = L"sndvol32.exe";
+    argument = "-R";
+  } else {
+    program = L"control.exe";
+    argument = "mmsys.cpl,,1";
+  }
+
+  FilePath path;
+  PathService::Get(base::DIR_SYSTEM, &path);
+  path = path.Append(program);
+  CommandLine command_line(path);
+  command_line.AppendArg(argument);
+  base::LaunchApp(command_line, false, false, NULL);
+}
+
 // static
 AudioManager* AudioManager::CreateAudioManager() {
   return new AudioManagerWin();