Add dart:io stubs to ddc sdk, define dart.library.html

pkg/dev_compiler/lib/src/compiler/compiler.dart

 // Copyright (c) 2016, 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:collection' show HashSet, Queue;
 import 'dart:convert' show BASE64, JSON, UTF8;
 import 'dart:io' show File;
 import 'package:analyzer/dart/element/element.dart' show LibraryElement;
 import 'package:analyzer/analyzer.dart'
     show AnalysisError, CompilationUnit, ErrorSeverity;
@@ skipping 79 matching lines @@
         resourceProvider: resourceProvider);
 
     var context = createAnalysisContext();
     context.sourceFactory = srcFactory;
     context.typeProvider = sdkResolver.dartSdk.context.typeProvider;
     context.resultProvider =
         new InputPackagesResultProvider(context, summaryData);
     options.declaredVariables.forEach(context.declaredVariables.define);
     context.declaredVariables.define('dart.isVM', 'false');
 
+    // TODO(vsm): Should this be hardcoded?

[Brian Wilkerson, 2016/12/14 20:28:41]

If you mean "hardcoded here" then I'd say this is fine, at least for now. There
was some discussion at one point of adding this information to the SDK (maybe in
the libraries.dart file?), but that hasn't happened yet as far as I know.

+    context.declaredVariables.define('dart.library.html', 'true');
+    context.declaredVariables.define('dart.library.io', 'false');
+
     return new ModuleCompiler.withContext(context, summaryData);
   }
 
   bool _isFatalError(AnalysisError e, CompilerOptions options) {
     if (errorSeverity(context, e) != ErrorSeverity.ERROR) return false;
 
     // These errors are not fatal in the REPL compile mode as we
     // allow access to private members across library boundaries
     // and those accesses will show up as undefined members unless
     // additional analyzer changes are made to support them.
@@ skipping 444 matching lines @@
     // Fall back to a relative path.
     return path.toUri(path.relative(path.fromUri(uri), from: dir)).toString();
   }
 
   for (int i = 0; i < list.length; i++) {
     list[i] = transformUri(list[i]);
   }
   map['file'] = transformUri(map['file']);
   return map;
 }