Add a flag for building skyx packages

sky/apk/rules.gni

Index: sky/apk/rules.gni
diff --git a/sky/apk/rules.gni b/sky/apk/rules.gni
index 87d59a40a4f9baf70554d4d93ede06ab55b25f13..27715b81ba72d08cf58f218865cf67ceef1b3b13 100644
--- a/sky/apk/rules.gni
+++ b/sky/apk/rules.gni
@@ -5,6 +5,15 @@
 import("//build/config/android/config.gni")
 import("//build/config/android/rules.gni")
 
+declare_args() {
+  # Controls whether we build app.skyx bundles in the sky_app template below.
+  # An app.skyx bundle contains all the code an resources needed to run a Sky
+  # app offline. Unfortunately, we don't yet have all the Dart packages we need
+  # to create skyx packages installed on the build bots, so this functionality
+  # is currently disabled. This flag allows for local testing of this feature.
+  enable_skyx = false
+}
+
 package_root = "$root_gen_dir/dart-pkg/packages"
 
 template("sky_apk") {
@@ -63,38 +72,36 @@ template("sky_app") {
     ]
   }
 
-  if (defined(invoker.sky_yaml)) {
-    app_bundle = "$target_gen_dir/${target_name}.skyx"
-
-    action("gen_bundle") {
-      asset_base = "$package_root/sky/assets/material-design-icons"
-      sky_yaml = invoker.sky_yaml
-
-      sources = [
-        sky_yaml,
-        snapshot,
-      ]
-
-      outputs = [
-        app_bundle,
-      ]
-
-      script = "//sky/tools/skyx.py"
-
-      args = [
-        rebase_path(sky_yaml, root_build_dir),
-        "--asset-base",
-        rebase_path(asset_base, root_build_dir),
-        "--snapshot",
-        rebase_path(snapshot, root_build_dir),
-        "-o",
-        rebase_path(app_bundle, root_build_dir),
-      ]
-
-      deps = [
-        ":gen_snapshot",
-      ]
-    }
+  app_bundle = "$target_gen_dir/app.skyx"
+
+  action("gen_bundle") {
+    asset_base = "$package_root/sky/assets/material-design-icons"
+    sky_yaml = invoker.sky_yaml
+
+    sources = [
+      "//sky/tools/skyx/bin/skyx.dart",
+      sky_yaml,
+      snapshot,
+    ]
+
+    outputs = [
+      app_bundle,
+    ]
+
+    script = "//sky/tools/skyx.py"
+    args = [
+      "--asset-base",
+      rebase_path(asset_base, root_build_dir),
+      "--snapshot",
+      rebase_path(snapshot, root_build_dir),
+      "-o",
+      rebase_path(app_bundle, root_build_dir),
+      rebase_path(sky_yaml, root_build_dir),
+    ]
+
+    deps = [
+      ":gen_snapshot",
+    ]
   }
 
   copy_ex("assets") {
@@ -103,12 +110,16 @@ template("sky_app") {
 
     sources = [
       "$root_build_dir/icudtl.dat",
-      "$target_gen_dir/snapshot_blob.bin",
     ]
 
     deps = [
       "//third_party/icu",
     ]
+
+    if (enable_skyx) {
+      sources += [ app_bundle ]
+      deps += [ ":gen_bundle" ]
+    }
   }
 
   android_apk(target_name) {
@@ -124,7 +135,6 @@ template("sky_app") {
       "//sky/shell:java",
       "//sky/shell:sky_shell",
       ":assets",
-      ":gen_snapshot",
     ]
 
     if (defined(invoker.deps)) {