gitc: delete a few more dead references

Change-Id: I1da6f2ee799c735a63ac3ca6e5abd1211af10433
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/419217
Reviewed-by: Josip Sokcevic <sokcevic@google.com>
Tested-by: Mike Frysinger <vapier@google.com>
Commit-Queue: Mike Frysinger <vapier@google.com>

manifest_xml.py

@@ -435,11 +435,6 @@ class XmlManifest:
         self.parent_groups = parent_groups
         self.default_groups = default_groups
 
-        if outer_client and self.isGitcClient:
-            raise ManifestParseError(
-                "Multi-manifest is incompatible with `gitc-init`"
-            )
-
         if submanifest_path and not outer_client:
             # If passing a submanifest_path, there must be an outer_client.
             raise ManifestParseError(f"Bad call to {self.__class__.__name__}")
@@ -2290,7 +2285,6 @@ class RepoClient(XmlManifest):
             submanifest_path: The submanifest root relative to the repo root.
             **kwargs: Additional keyword arguments, passed to XmlManifest.
         """
-        self.isGitcClient = False
         submanifest_path = submanifest_path or ""
         if submanifest_path:
             self._CheckLocalPath(submanifest_path)

project.py

@@ -1462,8 +1462,6 @@ class Project:
         self._InitHooks()
 
     def _CopyAndLinkFiles(self):
-        if self.client.isGitcClient:
-            return
         for copyfile in self.copyfiles:
             copyfile._Copy()
         for linkfile in self.linkfiles: