Remove unreachable code

Change 9bb1816b removed part of a block of code, but left the
remaining part unreachable.  Remove it.

Change-Id: Icdc6061d00e6027df32dee9a3bad3999fe7cdcbc

subcmds/sync.py

@@ -510,14 +510,6 @@ uncommitted changes are present' % project.relpath
         # bail out now; the rest touches the working tree
         return
 
-        self.manifest._Unload()
-        all = self.GetProjects(args, missing_ok=True)
-        missing = []
-        for project in all:
-          if project.gitdir not in fetched:
-            missing.append(project)
-        self._Fetch(missing, opt)
-
     if self.manifest.IsMirror:
       # bail out now, we have no working tree
       return