Qualify library names in packages

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 'package:args/args.dart' show ArgParser, ArgResults;
 import 'package:analyzer/analyzer.dart'
     show AnalysisError, CompilationUnit, ErrorSeverity;
 import 'package:analyzer/src/generated/engine.dart' show AnalysisContext;
 import 'package:analyzer/src/generated/java_engine.dart' show AnalysisException;
 import 'package:analyzer/src/generated/source_io.dart' show Source, SourceKind;
@@ skipping 178 matching lines @@
         help: 'Compile code even if it has errors. ಠ_ಠ\n'
             'This has undefined behavior!',
         defaultsTo: false);
 }
 
 /// A unit of Dart code that can be built into a single JavaScript module.
 class BuildUnit {
   /// The name of this module.
   final String name;
 
+  /// Build root.  All library names are relative to this path/prefix.
+  final String buildRoot;
+
   /// The list of sources in this module.
   ///
   /// The set of Dart files can be arbitrarily large, but it must contain
   /// complete libraries including all of their parts, as well as all libraries
   /// that are part of a library cycle.
   final List<String> sources;
 
   /// Given an imported library URI, this will determine to what Dart/JS module
   /// it belongs to.
   // TODO(jmesserly): we should replace this with another way of tracking
   // build units.
   final Func1<Source, String> libraryToModule;
 
-  BuildUnit(this.name, this.sources, this.libraryToModule);
+  BuildUnit(this.name, this.buildRoot, this.sources, this.libraryToModule);
 }
 
 /// The output of Dart->JS compilation.
 ///
 /// This contains the file contents of the JS module, as well as a list of
 /// Dart libraries that are contained in this module.
 class JSModuleFile {
   /// The name of this module.
   final String name;
 
@@ skipping 36 matching lines @@
 
     var map = new Map.from(this.sourceMap);
     List list = new List.from(map['sources']);
     map['sources'] = list;
     for (int i = 0; i < list.length; i++) {
       list[i] = path.relative(list[i], from: dir);
     }
     return map;
   }
 }