Add IPC to query capabilities of video input devices.

content/browser/BUILD.gn

 # Copyright 2014 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("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//media/media_options.gni")
 import("//ppapi/features/features.gni")
 import("//printing/features/features.gni")
 import("//third_party/WebKit/public/public_features.gni")
@@ skipping 870 matching lines @@
     "media/capture/web_contents_audio_input_stream.cc",
     "media/capture/web_contents_audio_input_stream.h",
     "media/capture/web_contents_audio_muter.cc",
     "media/capture/web_contents_audio_muter.h",
     "media/capture/web_contents_tracker.cc",
     "media/capture/web_contents_tracker.h",
     "media/cdm_registry_impl.cc",
     "media/cdm_registry_impl.h",
     "media/media_devices_permission_checker.cc",
     "media/media_devices_permission_checker.h",
+    "media/media_devices_util.cc",
+    "media/media_devices_util.h",
     "media/media_interface_proxy.cc",
     "media/media_interface_proxy.h",
     "media/media_internals.cc",
     "media/media_internals.h",
     "media/media_internals_handler.cc",
     "media/media_internals_handler.h",
     "media/media_internals_proxy.cc",
     "media/media_internals_proxy.h",
     "media/media_internals_ui.cc",
     "media/media_internals_ui.h",
@@ skipping 1117 matching lines @@
   if (!is_component_build) {
     public_deps = [
       ":browser",
     ]
   } else {
     public_deps = [
       "//third_party/leveldatabase",
     ]
   }
 }