Many type fixes.

lib/compiler/implementation/compile_time_constants.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.
 
 class Constant implements Hashable {
   const Constant();
 
   bool isNull() => false;
   bool isBool() => false;
   bool isTrue() => false;
@@ skipping 777 matching lines @@
     return new StringConstant(new DartString.concat(left.value, right.value));
   }
 
   Constant visitStringInterpolation(StringInterpolation node) {
     StringConstant initialString = evaluate(node.string);
     DartString accumulator = initialString.value;
     for (StringInterpolationPart part in node.parts) {
       Constant expression = evaluate(part.expression);
       DartString expressionString;
       if (expression.isNum() || expression.isBool()) {
-        Object value = expression.value;
-        expressionString = new DartString.literal(value.toString());
+        PrimitiveConstant primitive = expression;
+        expressionString = new DartString.literal(primitive.value.toString());
       } else if (expression.isString()) {
-        expressionString = expression.value;
+        PrimitiveConstant primitive = expression;
+        expressionString = primitive.value;
       } else {
         error(part.expression);
       }
       accumulator = new DartString.concat(accumulator, expressionString);
       StringConstant partString = evaluate(part.string);
       accumulator = new DartString.concat(accumulator, partString.value);
     };
     return new StringConstant(accumulator);
   }
 
@@ skipping 313 matching lines @@
       Constant fieldValue = fieldValues[field];
       if (fieldValue === null) {
         // Use the default value.
         fieldValue = compiler.compileVariable(field);
       }
       jsNewArguments.add(fieldValue);          
     });
     return jsNewArguments;
   }
 }