Fix PyAuto breakage introduced by 148809.

chrome/test/pyautolib/pyauto.py

Index: chrome/test/pyautolib/pyauto.py
diff --git a/chrome/test/pyautolib/pyauto.py b/chrome/test/pyautolib/pyauto.py
index 120a4de811ec21166d4978606dd8cc020311d59f..37bea02c50a7357fc8a633d6dc2a24a652795b1a 100755
--- a/chrome/test/pyautolib/pyauto.py
+++ b/chrome/test/pyautolib/pyauto.py
@@ -1966,8 +1966,8 @@ class PyUITest(pyautolib.PyUITestBase, unittest.TestCase):
       'tab_index': tab_index,
       'windex': windex,
     }
-    return FilePath(self._GetResultFromJSONRequest(cmd_dict,
-                                                   windex=None)['path'])
+    return FilePath(str(self._GetResultFromJSONRequest(cmd_dict,
+                                                       windex=None)['path']))
 
   def WaitForAllDownloadsToComplete(self, pre_download_ids=[], windex=0,
                                     timeout=-1):