Fixed too many files being open

pkg/docgen/lib/docgen.dart

Index: pkg/docgen/lib/docgen.dart
diff --git a/pkg/docgen/lib/docgen.dart b/pkg/docgen/lib/docgen.dart
index b31ef40f1c58755ec4783406f84c374de6bdc8b3..b960db74ecc4b5212e6951cdcd86cbbaa739360c 100644
--- a/pkg/docgen/lib/docgen.dart
+++ b/pkg/docgen/lib/docgen.dart
@@ -483,7 +483,7 @@ void _writeToFile(String text, String filename, {bool append: false}) {
   if (!file.existsSync()) {
     file.createSync();
   }
-  file.writeAsString(text, mode: append ? FileMode.APPEND : FileMode.WRITE);
+  file.writeAsStringSync(text, mode: append ? FileMode.APPEND : FileMode.WRITE);

[Emily Fortuna, 2013/08/08 21:07:56]

did you time this on linux? does this increase the run time? If so, could you
maybe just run the async version on linux and the sync version on mac?

[Tate Mandel, 2013/08/08 21:19:13]

I ran each version several times on Linux. 
This version ran in 8.0 +- .2sec every time.
The original ran in 10.0 +- .2sec every time.

Both writeAsString and writeAsStringSync claim to close the file after writing
to it in the docs, but it doesn't seem to be true for the former. The extra
memory usage could cause it to be slower despite being asynchronous.

[Emily Fortuna, 2013/08/08 21:58:22]

Curious! Well, I'm convinced! After you submit this, can you file a bug at
dartbug.com/new about this? People with the io library should investigate what's
going on and make sure it's actually doing what they intend it to be doing. :-)

 }
 
 /**