Tighten types in test.dart even more.

tools/testing/dart/status_reporter.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // 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:io';
 import 'dart:convert';
 
 final LINUX_COMBINATIONS = [
   {
     'runtimes': ['none'],
@@ skipping 131 matching lines @@
   var combinations = getCombinations();
 
   var arches = new Set<String>();
   var modes = new Set<String>();
 
   if (args.contains('--simple')) {
     arches = ['ia32'].toSet();
     modes = ['release'].toSet();
   } else {
     for (var combo in combinations) {
-      arches.addAll(combo['archs']);
-      modes.addAll(combo['modes']);
+      arches.addAll(combo['archs'] as List<String>);
+      modes.addAll(combo['modes'] as List<String>);
     }
   }
 
   ensureBuild(modes, arches);
 
   List<String> keys;
   for (var combination in combinations) {
     for (var mode in combination['modes']) {
       if (!modes.contains(mode)) {
         continue;
       }
 
       for (var arch in combination['archs']) {
         if (!arches.contains(arch)) {
           continue;
         }
 
         for (var runtime in combination['runtimes']) {
-          var compiler = combination['compiler'];
+          var compiler = combination['compiler'] as String;
 
           var args = [
             'tools/test.py',
             '-m$mode',
             '-c$compiler',
             '-r$runtime',
             '-a$arch',
             '--report-in-json',
             '--use-sdk'
           ];
           var result = Process.runSync('python', args);
           if (result.exitCode != 0) {
             print(result.stdout);
             print(result.stderr);
             throw new Exception("Error running: ${args.join(" ")}");
           }
 
           // Find "JSON:"
           // Everything after will the JSON-formatted output
           // per --report-in-json flag above
-          var totalIndex = result.stdout.indexOf('JSON:');
-          var report = result.stdout.substring(totalIndex + 5);
+          var totalIndex = (result.stdout as String).indexOf('JSON:');
+          var report = (result.stdout as String).substring(totalIndex + 5);
 
           var map = JSON.decode(report) as Map<String, int>;
 
           if (keys == null) {
             keys = map.keys.toList();
             var firstKey = keys.removeAt(0);
             if (firstKey != 'total') {
               throw '"total" should be the first key';
             }
 
@@ skipping 13 matching lines @@
             var pct = 100 * (value / total);
             values.add('${pct.toStringAsFixed(3)}%');
           }
 
           print(values.join(','));
         }
       }
     }
   }
 }