[ios] Adds a provider API for AudioSessionController.

ios/public/provider/chrome/browser/voice/voice_search_provider.mm

Index: ios/public/provider/chrome/browser/voice/voice_search_provider.mm
diff --git a/ios/public/provider/chrome/browser/voice/voice_search_provider.mm b/ios/public/provider/chrome/browser/voice/voice_search_provider.mm
new file mode 100644
index 0000000000000000000000000000000000000000..a7fa889f2ebf9364d207e946965b30e6d9d42500
--- /dev/null
+++ b/ios/public/provider/chrome/browser/voice/voice_search_provider.mm
@@ -0,0 +1,17 @@
+// Copyright 2016 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.
+
+#import "ios/public/provider/chrome/browser/voice/voice_search_provider.h"
+
+namespace ios {
+
+NSArray* VoiceSearchProvider::GetAvailableVoiceSearchLanguages() const {
+  return [NSArray array];

[sdefresne, 2016/10/18 22:19:44]

nit:

    return @[];

[rohitrao (ping after 24h), 2016/10/18 23:30:44]

Done.

+}
+
+AudioSessionController* VoiceSearchProvider::GetAudioSessionController() const {
+  return nil;
+}
+
+}  // namespace ios