Revert "bot_update: Don't force solutions to be unmanaged."

This reverts commit c48318a35b.

Reason for revert: likely broke ChromeOS

Original change's description:
> bot_update: Don't force solutions to be unmanaged.
> 
> gclient should be the one syncing the solutions to the appropriate
> revisions.
> 
> Bug: 850812, 853032
> Change-Id: Ieefc5661627d4864deb0d4e7053168a99da29d29
> Reviewed-on: https://chromium-review.googlesource.com/1102833
> Reviewed-by: Aaron Gable <agable@chromium.org>
> Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>

TBR=hinoka@chromium.org,agable@chromium.org,ehmaldonado@chromium.org

Change-Id: I7e110108a9687d703ea8be39cc83e0888f7813c6
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 850812, 853032, 855700
Reviewed-on: https://chromium-review.googlesource.com/1111925
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>
Commit-Queue: Andrii Shyshkalov <tandrii@chromium.org>

recipes/recipe_modules/bot_update/resources/bot_update.py

@@ -572,6 +572,26 @@ def get_target_pin(solution_name, git_url, revisions):
   return None
 
 
+def force_solution_revision(solution_name, git_url, revisions, cwd):
+  branch, revision = _get_target_branch_and_revision(
+      solution_name, git_url, revisions)
+  if revision and revision.upper() != 'HEAD':
+    treeish = revision
+  else:
+    # TODO(machenbach): This won't work with branch-heads, as Gerrit's
+    # destination branch would be e.g. refs/branch-heads/123. But here
+    # we need to pass refs/remotes/branch-heads/123 to check out.
+    # This will also not work if somebody passes a local refspec like
+    # refs/heads/master. It needs to translate to refs/remotes/origin/master
+    # first. See also https://crbug.com/740456 .
+    treeish = branch if branch.startswith('refs/') else 'origin/%s' % branch
+
+  # Note that -- argument is necessary to ensure that git treats `treeish`
+  # argument as revision or ref, and not as a file/directory which happens to
+  # have the exact same name.
+  git('checkout', '--force', treeish, '--', cwd=cwd)
+
+
 def _has_in_git_cache(revision_sha1, git_cache_dir, url):
   """Returns whether given revision_sha1 is contained in cache of a given repo.
   """
@@ -721,6 +741,8 @@ def _git_checkout(sln, sln_dir, revisions, shallow, refs, git_cache_dir,
       if sys.platform.startswith('win'):
         _maybe_break_locks(sln_dir, tries=3)
 
+      force_solution_revision(name, url, revisions, sln_dir)
+      git('clean', '-dff', cwd=sln_dir)
       return
     except SubprocessFailed as e:
       # Exited abnormally, theres probably something wrong.
@@ -894,6 +916,16 @@ def ensure_checkout(solutions, revisions, first_sln, target_os, target_os_only,
   # Windows sometimes has trouble deleting files. This can make git commands
   # that rely on locks fail.
   break_repo_locks = True if sys.platform.startswith('win') else False
+  # We want to pass all non-solution revisions into the gclient sync call.
+  solution_dirs = {sln['name'] for sln in solutions}
+  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'
 
   with git_config_if_not_set('user.name', 'chrome-bot'):
     with git_config_if_not_set('user.email', 'chrome-bot@chromium.org'):
@@ -904,7 +936,7 @@ def ensure_checkout(solutions, revisions, first_sln, target_os, target_os_only,
           BRANCH_HEADS_REFSPEC in refs,
           TAGS_REFSPEC in refs,
           shallow,
-          revisions,
+          gc_revisions,
           break_repo_locks,
           disable_syntax_validation,
           gerrit_repo,

tests/bot_update_coverage_test.py

@@ -211,7 +211,7 @@ class BotUpdateUnittests(unittest.TestCase):
     idx_second_revision = args.index(
         '--revision', idx_first_revision+1)
     idx_third_revision = args.index('--revision', idx_second_revision+1)
-    self.assertEquals(args[idx_first_revision+1], 'somename@DNE')
+    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