Move home.dart into example/demo_launcher

sky/sdk/example/demo_launcher/BUILD.gn

Index: sky/sdk/example/demo_launcher/BUILD.gn
diff --git a/sky/sdk/example/stocks/BUILD.gn b/sky/sdk/example/demo_launcher/BUILD.gn
similarity index 70%
copy from sky/sdk/example/stocks/BUILD.gn
copy to sky/sdk/example/demo_launcher/BUILD.gn
index 0173673ef4912182d386bf0eb288c02979188769..aec71dc7fe7dfac959054419cf844fe3e0782a88 100644
--- a/sky/sdk/example/stocks/BUILD.gn
+++ b/sky/sdk/example/demo_launcher/BUILD.gn
@@ -2,12 +2,9 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-assert(is_android)
+import("//sky/build/skyx.gni")
 
-import("//sky/apk/rules.gni")
-
-sky_app("stocks") {
-  apk_name = "Stocks"
+skyx("demo_launcher") {
   main_dart = "lib/main.dart"
   manifest = "sky.yaml"
 }