Move ListSubmodules into InputApi

Change-Id: Ia37291aca59b429b59bdc6424a2f36394d558e3f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/5214265
Auto-Submit: Joanna Wang <jojwang@chromium.org>
Commit-Queue: Joanna Wang <jojwang@chromium.org>
Commit-Queue: Josip Sokcevic <sokcevic@chromium.org>
Reviewed-by: Josip Sokcevic <sokcevic@chromium.org>

presubmit_support.py

@@ -879,6 +879,10 @@ class InputApi(object):
         self._named_temporary_files.append(temp_file.name)
         return temp_file
 
+    def ListSubmodules(self):
+        """Returns submodule paths for current change's repo."""
+        return scm.GIT.ListSubmodules(self.change.RepositoryRoot())
+
     @property
     def tbr(self):
         """Returns if a change is TBR'ed."""
@@ -1336,10 +1340,6 @@ class Change(object):
         """Convenience function."""
         return [af.AbsoluteLocalPath() for af in self.AffectedFiles()]
 
-    def ListSubmodules(self):
-        """Returns submodule paths for current change's repo."""
-        return scm.GIT.ListSubmodules(self.change.RepositoryRoot())
-
     def RightHandSideLines(self):
         """An iterator over all text lines in 'new' version of changed files.