Fix checkout error when depth passed to repo init and revision is a sha1

Currently, if direct fetch of a sha1 is not supported by git server and
depth option is used, we fallback on syncing the upstream branch by
ignoring depth option.

This fallback doesn't work in next 2 cases:
(1) upstream attribute is not specified in manifest
(2) depth option is passed to repo init command
    (not with clone-depth attribute in manifest)

This commit do the following:
- fixes (1) by updating condition used to apply fallback
  first we retry with depth set to None, then by syncing all branches
- fixes (2) by passing depth as argument of _RemoteFetch() method
  thus, its value is not set again to depth value passed to repo init
  command when applying fallback

Change-Id: Ifd6fffafc49ba229df624b0d7b64c83d47619d17

project.py

@@ -1258,13 +1258,18 @@ class Project(object):
       elif self.manifest.default.sync_c:
         current_branch_only = True
 
+    if self.clone_depth:
+      depth = self.clone_depth
+    else:
+      depth = self.manifest.manifestProject.config.GetString('repo.depth')
+
     need_to_fetch = not (optimized_fetch and
                          (ID_RE.match(self.revisionExpr) and
                           self._CheckForSha1()))
     if (need_to_fetch and
         not self._RemoteFetch(initial=is_new, quiet=quiet, alt_dir=alt_dir,
                               current_branch_only=current_branch_only,
-                              no_tags=no_tags, prune=prune)):
+                              no_tags=no_tags, prune=prune, depth=depth)):
       return False
 
     if self.worktree:
@@ -1880,23 +1885,17 @@ class Project(object):
                    quiet=False,
                    alt_dir=None,
                    no_tags=False,
-                   prune=False):
+                   prune=False,
+                   depth=None):
 
     is_sha1 = False
     tag_name = None
-    depth = None
-
     # The depth should not be used when fetching to a mirror because
     # it will result in a shallow repository that cannot be cloned or
     # fetched from.
-    if not self.manifest.IsMirror:
-      if self.clone_depth:
-        depth = self.clone_depth
-      else:
-        depth = self.manifest.manifestProject.config.GetString('repo.depth')
-      # The repo project should never be synced with partial depth
-      if self.relpath == '.repo/repo':
-        depth = None
+    # The repo project should also never be synced with partial depth.
+    if self.manifest.IsMirror or self.relpath == '.repo/repo':
+      depth = None
 
     if depth:
       current_branch_only = True
@@ -2057,21 +2056,22 @@ class Project(object):
           os.remove(packed_refs)
       self.bare_git.pack_refs('--all', '--prune')
 
-    if is_sha1 and current_branch_only and self.upstream:
+    if is_sha1 and current_branch_only:
       # We just synced the upstream given branch; verify we
       # got what we wanted, else trigger a second run of all
       # refs.
       if not self._CheckForSha1():
-        if not depth:
-          # Avoid infinite recursion when depth is True (since depth implies
-          # current_branch_only)
-          return self._RemoteFetch(name=name, current_branch_only=False,
-                                   initial=False, quiet=quiet, alt_dir=alt_dir)
-        if self.clone_depth:
-          self.clone_depth = None
+        if current_branch_only and depth:
+          # Sync the current branch only with depth set to None
           return self._RemoteFetch(name=name,
                                    current_branch_only=current_branch_only,
-                                   initial=False, quiet=quiet, alt_dir=alt_dir)
+                                   initial=False, quiet=quiet, alt_dir=alt_dir,
+                                   depth=None)
+        else:
+          # Avoid infinite recursion: sync all branches with depth set to None
+          return self._RemoteFetch(name=name, current_branch_only=False,
+                                   initial=False, quiet=quiet, alt_dir=alt_dir,
+                                   depth=None)
 
     return ok