Perform copy file activity when creating a new work directory

Performance improvements in repo sync caused us to skip out of the
initial Sync_LocalHalf without ever running CopyFiles, so we didn't
create the top level Makefile in new clients whose manifest request
one with a <copyfile> element.

Now we run CopyFiles after the initial read-tree that populates
the project working directory.

Signed-off-by: Shawn O. Pearce <sop@google.com>

project.py

@@ -1137,6 +1137,7 @@ class Project(object):
       cmd.append('HEAD')
       if GitCommand(self, cmd).Wait() != 0:
         raise GitError("cannot initialize work tree")
+      self._CopyFiles()
 
   def _gitdir_path(self, path):
     return os.path.join(self.gitdir, path)