[Mojo Video Capture] Stop service when last client disconnects.

services/video_capture/public/cpp/BUILD.gn

Index: services/video_capture/public/cpp/BUILD.gn
diff --git a/services/video_capture/public/cpp/BUILD.gn b/services/video_capture/public/cpp/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..4362d256f6de554830c7769b6da2aac1391869e6
--- /dev/null
+++ b/services/video_capture/public/cpp/BUILD.gn
@@ -0,0 +1,24 @@
+# Copyright 2017 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.
+
+source_set("cpp") {
+  sources = [
+    "device_to_feedback_observer_adapter.cc",
+    "device_to_feedback_observer_adapter.h",
+    "receiver_media_to_mojo_adapter.cc",
+    "receiver_media_to_mojo_adapter.h",
+  ]
+
+  public_deps = [
+    "//base",
+    "//media",
+    "//media/capture:capture",
+    "//services/service_manager/public/cpp",
+    "//services/video_capture/public/interfaces",
+  ]
+
+  deps = [
+    "//mojo/public/cpp/bindings:bindings",
+  ]
+}