The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/35090794b31bebd83423e7312f26191e3c39101d

commit 35090794b31bebd83423e7312f26191e3c39101d
Author: Marina Ciocea <marinaciocea@chromium.org>
Date: Mon May 07 07:54:23 2018

Add UI thread KeyboardMicRegistration implementation.

Used by AudioInputStreamBroker (introduced in dependent CL) instead of
AudioInputDeviceManager::KeyboardMicRegistration implementation, in order to avoid thread jumps and
to keep broker interface simple.

AudioInputDeviceManager::KeyboardMicRegistration will be removed after switching to audio service
input streams.

Bug:  828868 
Change-Id: I41aac3e01faeb0d4d47f98726bc069640fb346e3
Reviewed-on: https://chromium-review.googlesource.com/1044216
Commit-Queue: Marina Ciocea <marinaciocea@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Max Morin <maxmorin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#556390}
[modify] https://crrev.com/35090794b31bebd83423e7312f26191e3c39101d/content/browser/BUILD.gn
[modify] https://crrev.com/35090794b31bebd83423e7312f26191e3c39101d/content/browser/browser_main_loop.h
[add] https://crrev.com/35090794b31bebd83423e7312f26191e3c39101d/content/browser/media/keyboard_mic_registration.cc
[add] https://crrev.com/35090794b31bebd83423e7312f26191e3c39101d/content/browser/media/keyboard_mic_registration.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/003ff60f10c74b2bf95bfdc5b749faca6fb66050

commit 003ff60f10c74b2bf95bfdc5b749faca6fb66050
Author: Marina Ciocea <marinaciocea@chromium.org>
Date: Mon May 07 11:51:33 2018

Add AudioInputStreamBroker and create input streams using ForwardingAudioStreamFactory.

Both objects live in browser process. AudioInputStreamBroker maintains and observes state
of an input stream. ForwardingAudioStreamFactory forwards stream creation to audio::StreamFactory
in audio service process.

AudioInputStreamBroker implements media::mojom::AudioInputStreamObserver, replacing media::MojoAISObserver.

Bug:  828868 
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
Change-Id: Ieabb77c2edfd7e9939e6f7cd43b953d2af1d1c2c
Reviewed-on: https://chromium-review.googlesource.com/1030330
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Max Morin <maxmorin@chromium.org>
Commit-Queue: Marina Ciocea <marinaciocea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#556417}
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/BUILD.gn
[add] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/audio_input_stream_broker.cc
[add] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/audio_input_stream_broker.h
[add] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/audio_input_stream_broker_unittest.cc
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/audio_output_stream_broker.cc
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/audio_output_stream_broker_unittest.cc
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/audio_stream_broker.cc
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/audio_stream_broker.h
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/forwarding_audio_stream_factory.cc
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/forwarding_audio_stream_factory.h
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/browser/media/forwarding_audio_stream_factory_unittest.cc
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/content/test/BUILD.gn
[modify] https://crrev.com/003ff60f10c74b2bf95bfdc5b749faca6fb66050/media/mojo/services/BUILD.gn
[delete] https://crrev.com/102518734aaf1a344c8c874a3c5159c7156ef382/media/mojo/services/mojo_audio_input_stream_observer.cc
[delete] https://crrev.com/102518734aaf1a344c8c874a3c5159c7156ef382/media/mojo/services/mojo_audio_input_stream_observer.h
[delete] https://crrev.com/102518734aaf1a344c8c874a3c5159c7156ef382/media/mojo/services/mojo_audio_input_stream_observer_unittest.cc

[bulk-edit: disregard if N/A] Can the owner please set milestone to this bug if applicable?