Fix checked mode errors

lib/compiler/implementation/compiler.dart

 // Copyright (c) 2012, 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.
 
 
 /**
  * If true, print a warning for each method that was resolved, but not
  * compiled.
  */
 final bool REPORT_EXCESS_RESOLUTION = false;
@@ skipping 175 matching lines @@
       HType type = fieldInitializers[field.enclosingElement][field];
       return type == null ? HType.UNKNOWN : type;
     } else {
       return HType.UNKNOWN;
     }
   }
 
   void updateFieldSetters(Element field, HType type) {
     assert(field.isField());
     assert(field.enclosingElement.isClass());
-    Map<Element, bool> fields =
+    Map<Element, HType> fields =
         fieldSettersType.putIfAbsent(
           field.enclosingElement, () => new Map<Element, HType>());
     if (!fields.containsKey(field)) {
       fields[field] = type;
     } else {
       fields[field] = fields[field].union(type);
     }
   }
 
   // Returns whether nothing but setters setting the field to an integer have
   // been seen during compilation so far.
   HType fieldSettersTypeSoFar(Element field) {
     assert(field.isField());
     assert(field.enclosingElement.isClass());
     if (!fieldSettersType.containsKey(field.enclosingElement)) {
       return HType.UNKNOWN;
     }
-    Map<Element, Htype> fields = fieldSettersType[field.enclosingElement];
+    Map<Element, HType> fields = fieldSettersType[field.enclosingElement];
     if (!fields.containsKey(field)) return HType.UNKNOWN;
     return fields[field];
   }
 }
 
 class Compiler implements DiagnosticListener {
   final Map<String, LibraryElement> libraries;
   int nextFreeClassId = 0;
   World world;
   String assembledCode;
@@ skipping 769 matching lines @@
                      f(int beginOffset, int endOffset)) {
     final beginOffset = begin.charOffset;
     final endOffset = end.charOffset + end.slowCharCount;
 
     // [begin] and [end] might be the same for the same empty token. This
     // happens for instance when scanning '$$'.
     assert(endOffset >= beginOffset);
     return f(beginOffset, endOffset);
   }
 }