Make interactive_flex and mine_digger work offline

From SkyDemo.apk.

R=eseidel@chromium.org, eseidel@google.com

Review URL: https://codereview.chromium.org/1221143003 .

sdk/example/demo_launcher/BUILD.gn

@@ -12,7 +12,9 @@ sky_app("demo_launcher") {
   if (enable_skyx) {
     bundles = [
       "//sky/sdk/example/mine_digger",
+      "//sky/sdk/example/rendering:interactive_flex",
       "//sky/sdk/example/stocks",
+      "//sky/sdk/example/widgets:sector",
     ]
   }
 

sdk/example/demo_launcher/apk/org/domokit/sky/demo/SkyDemoApplication.java

@@ -26,7 +26,9 @@ import org.domokit.sky.shell.SkyApplication;
  */
 public class SkyDemoApplication extends SkyApplication {
     private static final String[] DEMO_RESOURCES = {
+        "interactive_flex.skyx",
         "mine_digger.skyx",
+        "sector.skyx",
         "stocks.skyx",
     };