Generate cached_patches.dart using new Dartium swtich

tools/dartium/generate_app/generate_cached_patches.dart

Index: tools/dartium/generate_app/generate_cached_patches.dart
diff --git a/tools/dartium/generate_app/generate_cached_patches.dart b/tools/dartium/generate_app/generate_cached_patches.dart
index 21ca4fb6f83bc4d5a1799e48e9bd5f1a8622eb92..af34b27ae01a0c5060d845a38f2afd40682cac09 100644
--- a/tools/dartium/generate_app/generate_cached_patches.dart
+++ b/tools/dartium/generate_app/generate_cached_patches.dart
@@ -2,12 +2,9 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import "dart:js" as js;
-
 void main() {
   try {
-    var cached_files = js.createCachedPatchesFile();
-    print("$cached_files");
+    print("Generated Patches");
   } catch (e) {
     var workedElem = document.querySelector("#worked");
     var failedElem = document.querySelector("#failed");