Mus Demo: Demonstrate external window mode

services/ui/demo/BUILD.gn

Index: services/ui/demo/BUILD.gn
diff --git a/services/ui/demo/BUILD.gn b/services/ui/demo/BUILD.gn
index cad0d5570e311c566548a991ab12b44b44ecd4ae..7d2c46063e41562a7a54c25609f59eeb46d61cd1 100644
--- a/services/ui/demo/BUILD.gn
+++ b/services/ui/demo/BUILD.gn
@@ -12,6 +12,8 @@ source_set("lib") {
   sources = [
     "mus_demo.cc",
     "mus_demo.h",
+    "mus_demo_external.cc",
+    "mus_demo_external.h",
     "mus_demo_internal.cc",
     "mus_demo_internal.h",
   ]
@@ -35,6 +37,20 @@ source_set("lib") {
   ]
 }
 
+service("mus_demo_external") {
+  sources = [
+    "main_external.cc",
+  ]
+
+  deps = [
+    ":lib",
+  ]
+
+  data_deps = [
+    "//services/ui",
+  ]
+}
+
 service("mus_demo_internal") {
   sources = [
     "main_internal.cc",
@@ -49,6 +65,11 @@ service("mus_demo_internal") {
   ]
 }
 
+service_manifest("manifest_external") {
+  name = "mus_demo_external"
+  source = "manifest_external.json"
+}
+
 service_manifest("manifest_internal") {
   name = "mus_demo_internal"
   source = "manifest_internal.json"
@@ -78,12 +99,14 @@ service_test("mus_demo_unittests") {
   ]
 
   data_deps = [
+    ":mus_demo_external",
     ":mus_demo_internal",
   ]
 }
 
 group("demo") {
   deps = [
+    ":mus_demo_external",
     ":mus_demo_internal",
   ]
 }
@@ -92,6 +115,7 @@ catalog("mus_demo_unittests_catalog") {
   embedded_services = [ ":test_manifest" ]
 
   standalone_services = [
+    ":manifest_external",
     ":manifest_internal",
     "//services/ui:manifest",
   ]