expose temporary_directory.

Since python2 tempfile does not have TemporaryDirectory, we need to either use temporary_directory in gclient_utils or implement it by ourselves.  If we chose latter, we also need to implement rmtree for Windows.  Considering that, I suppose using gclient_utils should be much easier.

Bug: 939959
Change-Id: Ife21a2bc297ac61a4c1940b06df937c293961ae7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1524815
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Yoshisato Yanagisawa <yyanagisawa@chromium.org>
Auto-Submit: Yoshisato Yanagisawa <yyanagisawa@chromium.org>

presubmit_support.py

@@ -518,6 +518,9 @@ class InputApi(object):
     self.cStringIO = cStringIO
     self.fnmatch = fnmatch
     self.gclient_paths = gclient_paths
+    # TODO(yyanagisawa): stop exposing this when python3 become default.
+    # Since python3's tempfile has TemporaryDirectory, we do not need this.
+    self.temporary_directory = gclient_utils.temporary_directory
     self.glob = glob.glob
     self.json = json
     self.logging = logging.getLogger('PRESUBMIT')

tests/presubmit_unittest.py

@@ -976,6 +976,7 @@ class InputApiUnittest(PresubmitTestsBase):
         'subprocess',
         'tbr',
         'tempfile',
+        'temporary_directory',
         'thread_pool',
         'time',
         'traceback',