Revert "[dynamo][guards] Fail on an unknown framelocals to dict conversion (pytorch#162695)"

This reverts commit a8432bc.

Reverted pytorch#162695 on behalf of https://github.com/anijain2305 due to internal failure at https://fburl.com/workplace/qiitdlp6 ([comment](pytorch#162695 (comment)))

Author: pytorchmergebot

torch/csrc/dynamo/guards.cpp

@@ -2695,7 +2695,9 @@ class GuardAccessor {
   // subtree on immutable dict getitems.
   virtual bool check_nopybind(PyObject* obj, bool matches_dict_tag = false) = 0;
   virtual bool check_nopybind(FrameLocalsMapping* map, bool matches_dict_tag) {
-    throw std::runtime_error("fallback to python");
+    // throw std::runtime_error("fallback to python");
+    // Could fallback to running check on the Python dict (lazily constructed)
+    return check_nopybind((PyObject*)map->to_dict(), matches_dict_tag);
   }
   virtual GuardDebugInfo check_verbose_nopybind(PyObject* obj) = 0;
   virtual std::string repr() const = 0;