Fix issue 420: accept truncated log files.

test/mjsunit/mjsunit.js

Index: test/mjsunit/mjsunit.js
diff --git a/test/mjsunit/mjsunit.js b/test/mjsunit/mjsunit.js
index 2c52a31e604451065363bc1fc90d1452a7b20427..1fb3f02afba9768109bee5dd34edcfdee3b0d12c 100644
--- a/test/mjsunit/mjsunit.js
+++ b/test/mjsunit/mjsunit.js
@@ -179,9 +179,13 @@ function assertInstanceof(obj, type) {
 
 function assertDoesNotThrow(code) {
   try {
-    eval(code);
+    if (typeof code == 'function') {
+      code();
+    } else {
+      eval(code);
+    }
   } catch (e) {
-    assertTrue(false, "threw an exception");
+    assertTrue(false, "threw an exception: " + (e.message || e));
   }
 }