Improve error reporting in benchmarks.

benchmarks/run.js

Index: benchmarks/run.js
===================================================================
--- benchmarks/run.js	(revision 549)
+++ benchmarks/run.js	(working copy)
@@ -33,17 +33,27 @@
 load('raytrace.js');
 load('earley-boyer.js');
 
+var success = true;
 
 function PrintResult(name, result) {
   print(name + ': ' + result);
 }
 
 
+function PrintError(name, error) {
+  PrintResult(name, error);
+  success = false;
+}
+
+
 function PrintScore(score) {
-  print('----');
-  print('Score (version ' + BenchmarkSuite.version + '): ' + score);
+  if (success) {
+    print('----');
+    print('Score (version ' + BenchmarkSuite.version + '): ' + score);
+  }
 }
 
 
 BenchmarkSuite.RunSuites({ NotifyResult: PrintResult,
+                           NotifyError: PrintError,
                            NotifyScore: PrintScore });