Fix most warnings and other minor cleanups.

lib/compiler/implementation/scanner/scanner_bench.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.
 
 #library('scanner_bench');
 #import('scannerlib.dart');
 #import('scanner_implementation.dart');
 #source('source_list.dart');
 
 /**
@@ skipping 15 matching lines @@
     for (int i = 0; i < iterations; i++) {
       bar.tick();
       Stopwatch timer = new Stopwatch();
       timer.start();
       int charCount = 0;
       for (final String argument in arguments) {
         charCount += tokenizeOne(argument);
       }
       timer.stop();
       bar.recordScore(charCount / timer.elapsedInMs());
-      log("Tokenized ${arguments.length} files " +
-          "(total size = ${charCount} chars) " +
+      log("Tokenized ${arguments.length} files "
+          "(total size = ${charCount} chars) "
           "in ${timer.elapsedInMs()}ms");
     }
     bar.end();
   }
 
   int tokenizeOne(String filename) {
     return getBytes(filename, (bytes) {
       Scanner scanner = makeScanner(bytes);
       try {
         printTokens(scanner.tokenize());
@@ skipping 93 matching lines @@
 
   void end() {
   }
 
   void recordScore(num score) {
     if (total > 10) {
       print("$ticks, $score, ${ticks * 100 ~/ total}%");
     }
   }
 }