Bot Update: Always pass in --revision <solution>@unmanaged

Gclient sometimes ignores "unmanaged": "False" in the gclient solution
if --revision <anything> is passed.  This forces gclient to always
treat solutions deps as unmanaged.

BUG=693296

Change-Id: I91d5f4c9377fab0fde23cf15d1475779978820fa
Reviewed-on: https://chromium-review.googlesource.com/444098
Commit-Queue: Andrii Shyshkalov <tandrii@chromium.org>
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>

recipe_modules/bot_update/resources/bot_update.py

@@ -807,6 +807,11 @@ def ensure_checkout(solutions, revisions, first_sln, target_os, target_os_only,
   gc_revisions = {
       dirname: rev for dirname, rev in revisions.iteritems()
       if dirname not in solution_dirs}
+  # Gclient sometimes ignores "unmanaged": "False" in the gclient solution
+  # if --revision <anything> is passed (for example, for subrepos).
+  # This forces gclient to always treat solutions deps as unmanaged.
+  for solution_name in list(solution_dirs):
+    gc_revisions[solution_name] = 'unmanaged'
   # Let gclient do the DEPS syncing.
   # The branch-head refspec is a special case because its possible Chrome
   # src, which contains the branch-head refspecs, is DEPSed in.

tests/bot_update_coverage_test.py

@@ -213,10 +213,10 @@ class BotUpdateUnittests(unittest.TestCase):
     idx_first_revision = args.index('--revision')
     idx_second_revision = args.index(
         '--revision', idx_first_revision+1)
-    with self.assertRaises(ValueError):
-      args.index('--revision', idx_second_revision+1)
-    self.assertEquals(args[idx_first_revision+1], 'src@origin/master')
-    self.assertEquals(args[idx_second_revision+1], 'src/v8@deadbeef')
+    idx_third_revision = args.index('--revision', idx_second_revision+1)
+    self.assertEquals(args[idx_first_revision+1], 'somename@unmanaged')
+    self.assertEquals(args[idx_second_revision+1], 'src@origin/master')
+    self.assertEquals(args[idx_third_revision+1], 'src/v8@deadbeef')
     return self.call.records
 
   def testBreakLocks(self):