git cl try: reduce number of RPCs to Gerrit from 3 to 1.

R=agable@chromium.org
BUG=681704

Change-Id: I3c0ab781e0357e0855d50157c5653df57f68ac9a
Reviewed-on: https://chromium-review.googlesource.com/432336Reviewed-by: Aaron Gable <agable@chromium.org>

git_cl.py

@@ -463,11 +463,6 @@ def _trigger_try_jobs(auth_config, changelist, buckets, options,
   http = authenticator.authorize(httplib2.Http())
   http.force_exception_to_status_code = True
 
-  # TODO(tandrii): consider caching Gerrit CL details just like
-  # _RietveldChangelistImpl does, then caching values in these two variables
-  # won't be necessary.
-  owner_email = changelist.GetIssueOwner()
-
   buildbucket_put_url = (
       'https://{hostname}/_ah/api/buildbucket/v1/builds/batch'.format(
           hostname=options.buildbucket_host))
@@ -498,7 +493,7 @@ def _trigger_try_jobs(auth_config, changelist, buckets, options,
       parameters = {
           'builder_name': builder,
           'changes': [{
-              'author': {'email': owner_email},
+              'author': {'email': changelist.GetIssueOwner()},
               'revision': options.revision,
           }],
           'properties': shared_parameters_properties.copy(),
@@ -4722,6 +4717,10 @@ def CMDtry(parser, args):
   if not cl.GetIssue():
     parser.error('Need to upload first')
 
+  if cl.IsGerrit():
+    # HACK: warm up Gerrit change detail cache to save on RPCs.
+    cl._codereview_impl._GetChangeDetail(['DETAILED_ACCOUNTS', 'ALL_REVISIONS'])
+
   error_message = cl.CannotTriggerTryJobReason()
   if error_message:
     parser.error('Can\'t trigger try jobs: %s' % error_message)

tests/git_cl_test.py

@@ -2278,8 +2278,24 @@ class TestGitCl(TestCase):
         ((['git', 'config', 'branch.feature.gerritissue'],), '123456'),
         ((['git', 'config', 'branch.feature.gerritserver'],),
          'https://chromium-review.googlesource.com'),
-        (('GetChangeDetail', 'chromium-review.googlesource.com', '123456', []),
-         { 'status': 'OPEN' }),
+        (('GetChangeDetail', 'chromium-review.googlesource.com', '123456',
+         ['DETAILED_ACCOUNTS', 'ALL_REVISIONS', 'CURRENT_COMMIT']), {
+          'project': 'depot_tools',
+          'status': 'OPEN',
+          'owner': {'email': 'owner@e.mail'},
+          'revisions': {
+            'deadbeaf':  {
+              '_number': 6,
+            },
+            'beeeeeef': {
+              '_number': 7,
+              'fetch': {'http': {
+                'url': 'https://chromium.googlesource.com/depot_tools',
+                'ref': 'refs/changes/56/123456/7'
+              }},
+            },
+          },
+        }),
         ((['git', 'config', 'branch.feature.merge'],), 'feature'),
         ((['git', 'config', 'branch.feature.remote'],), 'origin'),
         ((['get_or_create_merge_base', 'feature', 'feature'],),
@@ -2370,14 +2386,11 @@ class TestGitCl(TestCase):
         ((['git', 'config', 'branch.feature.gerritissue'],), '123456'),
         ((['git', 'config', 'branch.feature.gerritserver'],),
          'https://chromium-review.googlesource.com'),
-        (('GetChangeDetail', 'chromium-review.googlesource.com', '123456', []),
-         { 'status': 'OPEN' }),
-        (('GetChangeDetail', 'chromium-review.googlesource.com', '123456',
-         ['DETAILED_ACCOUNTS']),
-         {'owner': {'email': 'owner@e.mail'}}),
         (('GetChangeDetail', 'chromium-review.googlesource.com', '123456',
-         ['ALL_REVISIONS', 'CURRENT_COMMIT']), {
+         ['DETAILED_ACCOUNTS', 'ALL_REVISIONS', 'CURRENT_COMMIT']), {
           'project': 'depot_tools',
+          'status': 'OPEN',
+          'owner': {'email': 'owner@e.mail'},
           'revisions': {
             'deadbeaf':  {
               '_number': 6,