Check on the existence of report directory

Reports will be written at rtcBot/test/reports/<report_name>

R=andresp@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/26689004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7372 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/tools/rtcbot/test.js

@@ -121,9 +121,19 @@ StatisticsReport.prototype = {
   },
 
   finish: function (doneCallback) {
-    fs.writeFile("test/reports/" + this.outputFileName_ + "_" +
+    fs.exists("test/reports/", function (exists) {
+      if(exists) {
+        writeFile.bind(this)();
+      } else {
+        fs.mkdir("test/reports/", 0777, writeFile.bind(this));
+      }
+    }.bind(this));
+
+    function writeFile () {
+      fs.writeFile("test/reports/" + this.outputFileName_ + "_" +
         (new Date()).getTime() +".json", JSON.stringify(this.output_),
         doneCallback);
+    }
   },
 }