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

services/video_capture/public/interfaces/BUILD.gn

Index: services/video_capture/public/interfaces/BUILD.gn
diff --git a/services/video_capture/public/interfaces/BUILD.gn b/services/video_capture/public/interfaces/BUILD.gn
index 0d2001116f715192c3fc52e9226a8eb4d13285d6..8c3a3a4f6377070776a72cac5cbc54770ddc5a77 100644
--- a/services/video_capture/public/interfaces/BUILD.gn
+++ b/services/video_capture/public/interfaces/BUILD.gn
@@ -8,8 +8,8 @@ mojom("interfaces") {
   sources = [
     "device.mojom",
     "device_factory.mojom",
+    "device_factory_provider.mojom",
     "receiver.mojom",
-    "service.mojom",
   ]
 
   deps = [
@@ -18,3 +18,9 @@ mojom("interfaces") {
     "//ui/gfx/geometry/mojo",
   ]
 }
+
+mojom("constants") {
+  sources = [
+    "constants.mojom",
+  ]
+}