Add manual mode to VR bisect script

Adds an option to the VR bisect script to run in manual mode. This
removes the automatic "gclient sync" and waits for user input before
building and running the test. This is meant to be used in the rare case
that some change in the bisect range breaks gclient sync and requires
some DEPS change to fix. This allows the user to manually add in the fix
and sync while still allowing the script to handle the building,
running, and result retrieval.

Change-Id: I7bfd5b7b059dec84b3feefbbc6ada3e01659d30d
Reviewed-on: https://chromium-review.googlesource.com/1014460Reviewed-by: Tibor Goldschwendt <tiborg@chromium.org>
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#551374}

chrome/test/vr/auto_bisect.py

@@ -109,6 +109,13 @@ def ParseArgsAndAssertValid():
                       help='The data format the JSON results from the test are '
                            'expected to be in. Supported values are: ' +
                            (', '.join(SUPPORTED_JSON_RESULT_FORMATS.keys())))
+  parser.add_argument('--manual-mode', action='store_true', default=False,
+                      help='Does not automatically run gclient sync and waits '
+                           'for user input before starting the build/run '
+                           'process. Useful if a bisect needs to be run within '
+                           'a range where some change breaks gclient sync and '
+                           'a patch needs to be applied at each step before '
+                           'syncing.')
 
   parser.add_argument_group('swarming arguments')
   parser.add_argument('--swarming-server', required=True,
@@ -172,6 +179,9 @@ def VerifyInput(args, unknown_args):
     unknown_args: The unknown args parsed by the argument parser
   """
   print '======'
+  if args.manual_mode:
+    print ('Script is running in manual mode - you must manually run gclient '
+          'sync on each revision')
   print 'This will start a bisect for a for:'
   print 'Metric: %s' % args.metric
   print 'Story: %s' % args.story
@@ -395,10 +405,10 @@ def RunBisectStep(args, unknown_args, revision, output_dir):
   output = ""
   if revision_good:
     print '=== Current revision is GOOD ==='
-    output = subprocess.check_output(['git', 'bisect', 'good'])
+    output = subprocess.check_output(['git', 'bisect', 'good', revision])
   else:
     print '=== Current revision is BAD ==='
-    output = subprocess.check_output(['git', 'bisect', 'bad'])
+    output = subprocess.check_output(['git', 'bisect', 'bad', revision])
 
   print output
   if output.startswith('Bisecting:'):
@@ -414,20 +424,26 @@ def SyncAndBuild(args, unknown_args, revision):
     unknown_args: The unknown args parsed by the argument parser
     revision: The revision to sync to and build
   """
-  print '=== Syncing to revision %s and building ===' % revision
-  # Sometimes random files show up as unstaged changes (???), so make sure that
-  # isn't the case before we try to run gclient sync
-  if args.reset_before_sync:
-    subprocess.check_output(['git', 'reset', '--hard', 'HEAD'])
-  print 'Syncing'
-  output = subprocess.check_output(['gclient', 'sync', '-r',
-      'src@%s' % revision])
-  if ('error: Your local changes to the following files would be overwritten '
-      'by checkout:' in output):
-    raise RuntimeError('Could not run gclient sync due to uncommitted changes. '
-        'If these changes are actually yours, please commit or stash them. If '
-        'they are not, remove them and try again. If the issue persists, try '
-        'running with --reset-before-sync')
+  if args.manual_mode:
+    print ('=== Waiting on user input to start build/run process for %s ===' %
+        revision)
+    raw_input('Press any key to continue')
+    print '=== Building ==='
+  else:
+    print '=== Syncing to revision %s and building ===' % revision
+    # Sometimes random files show up as unstaged changes (???), so make sure
+    # that isn't the case before we try to run gclient sync
+    if args.reset_before_sync:
+      subprocess.check_output(['git', 'reset', '--hard', 'HEAD'])
+    print 'Syncing'
+    output = subprocess.check_output(['gclient', 'sync', '-r',
+        'src@%s' % revision])
+    if ('error: Your local changes to the following files would be overwritten '
+        'by checkout:' in output):
+      raise RuntimeError('Could not run gclient sync due to uncommitted '
+          'changes. If these changes are actually yours, please commit or '
+          'stash them. If they are not, remove them and try again. If the '
+          'issue persists, try running with --reset-before-sync')
 
   # Ensure that the VR assets are synced to the current revision since it isn't
   # guaranteed that gclient will handle it properly