Add a prefix to temporary file to enter CL description.

So that if the process dies in the middle, the files are easier to spot and
delete.

R=iannucci@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/19498004

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@213081 0039d316-1c4b-4281-b951-d872f2087c98

gclient_utils.py

@@ -806,7 +806,7 @@ def GetEditor(git, git_editor=None):
 
 def RunEditor(content, git, git_editor=None):
   """Opens up the default editor in the system to get the CL description."""
-  file_handle, filename = tempfile.mkstemp(text=True)
+  file_handle, filename = tempfile.mkstemp(text=True, prefix='cl_description')
   # Make sure CRLF is handled properly by requiring none.
   if '\r' in content:
     print >> sys.stderr, (