fix #29766, fix #29782 - fix override checker's interface checking

pkg/dev_compiler/tool/build_pkgs.dart

 #!/usr/bin/env dart
 import 'dart:io';
 
 import 'package:path/path.dart' as p;
 
 import 'package:dev_compiler/src/compiler/command.dart';
 
 final String scriptDirectory = p.dirname(p.fromUri(Platform.script));
 String outputDirectory;
 
@@ skipping 25 matching lines @@
   compileModule('expect', libs: ['minitest']);
   compileModule('js', libs: ['js_util']);
   compileModule('meta');
   if (isTravis) {
     compileModule('lookup_map');
     compileModule('microlytics', libs: ['html_channels']);
     compileModule('typed_mock');
   }
 
   // Under third_party/pkg.
-  compileModule('collection');
+  compileModule('collection', unsafeForceCompile: true);

[vsm, 2017/07/19 17:19:04]

This will probably break dartdevc snapshot generation too.  The snapshot is
built by compiling ddc against itself.  Looks like we import package:collection.

Can you land your fix there and roll it forward?  To roll forward, update this
to new tag or hash:

https://github.com/dart-lang/sdk/blob/master/DEPS#L61

[Jennifer Messerly, 2017/07/20 19:15:50]

done

   compileModule('matcher');
   compileModule('path');
   if (isTravis) {
     compileModule('args', libs: ['command_runner']);
     compileModule('charcode');
     compileModule('fixnum');
     compileModule('logging');
     compileModule('markdown');
     compileModule('mime');
     compileModule('plugin', libs: ['manager']);
@@ skipping 52 matching lines @@
   // but I'm not sure how they'll affect the other non-DDC tests. For now, just
   // use ours.
   if (module == 'async_helper') {
     args.add('--url-mapping=package:async_helper/async_helper.dart,' +
         p.join(scriptDirectory, "../test/codegen/async_helper.dart"));
   }
 
   var exitCode = compile(args);
   if (exitCode != 0) exit(exitCode);
 }