adding packages

deprecated/mobile_popup/example/windows/find_vcvars.dart

@@ -0,0 +1,35 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// This script attempts to find vcvars64.bat, and if successful outputs its
+// path and returns 0. Otherwise, it prints nothing and returns 1.
+import 'dart:io';
+
+int main() {
+  final programDir = Platform.environment['PROGRAMFILES(X86)'];
+  final pathPrefix = '$programDir\\Microsoft Visual Studio';
+  const pathSuffix = 'VC\\Auxiliary\\Build\\vcvars64.bat';
+  final years = ['2017', '2019'];
+  final flavors = ['Community', 'Professional', 'Enterprise', 'Preview'];
+  for (final year in years) {
+    for (final flavor in flavors) {
+      final testPath = '$pathPrefix\\$year\\$flavor\\$pathSuffix';
+      if (File(testPath).existsSync()) {
+        print(testPath);
+        return 0;
+      }
+    }
+  }
+  return 1;
+}