Make String.charCodes a getter.

utils/tests/string_encoding/benchmark_runner.dart

Index: utils/tests/string_encoding/benchmark_runner.dart
diff --git a/utils/tests/string_encoding/benchmark_runner.dart b/utils/tests/string_encoding/benchmark_runner.dart
index 65007d7b20c5912f256ab8afd19875d15bf49f87..9fc7bded12e5780d1906532388e1d784b60611c0 100644
--- a/utils/tests/string_encoding/benchmark_runner.dart
+++ b/utils/tests/string_encoding/benchmark_runner.dart
@@ -89,7 +89,7 @@ class PerformanceModel {
  */
 class TestReport {
   TestReport(this.id, this.desc, this.warmup, this.results) {
-    spaceChar = " ".charCodes()[0];
+    spaceChar = " ".charCodes[0];
   }
 
   int spaceChar;
@@ -169,7 +169,7 @@ class TestReport {
   String _leftAlign(String s, int width) {
     List<int> outCodes = [];
     outCodes.insertRange(0, width, spaceChar);
-    outCodes.setRange(0, Math.min(width, s.length), s.charCodes());
+    outCodes.setRange(0, Math.min(width, s.length), s.charCodes);
     return new String.fromCharCodes(outCodes);
   }
 
@@ -177,7 +177,7 @@ class TestReport {
     List<int> outCodes = [];
     outCodes.insertRange(0, width, spaceChar);
     outCodes.setRange(Math.max(0, width - s.length), Math.min(width, s.length),
-        s.charCodes());
+        s.charCodes);
     return new String.fromCharCodes(outCodes);
   }