Revert of mojo: Add a runloop utility in python

mojo/public/python/src/python_system_helper.cc

-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "mojo/public/python/src/python_system_helper.h"
-
-#include "Python.h"
-
-#include "mojo/public/cpp/environment/logging.h"
-#include "mojo/public/cpp/system/macros.h"
-#include "mojo/public/cpp/utility/run_loop.h"
-
-namespace {
-
-class ScopedGIL {
- public:
-  ScopedGIL() {
-    state_ = PyGILState_Ensure();
-  }
-
-  ~ScopedGIL() {
-    PyGILState_Release(state_);
-  }
-
- private:
-  PyGILState_STATE state_;
-
-  MOJO_DISALLOW_COPY_AND_ASSIGN(ScopedGIL);
-};
-
-class PythonClosure : public mojo::Closure::Runnable {
- public:
-  PythonClosure(PyObject* callable) : callable_(callable) {
-    MOJO_CHECK(callable);
-    Py_XINCREF(callable);
-  }
-
-  virtual ~PythonClosure() {
-    ScopedGIL acquire_gil;
-    Py_DECREF(callable_);
-  }
-
-  virtual void Run() const MOJO_OVERRIDE {
-    ScopedGIL acquire_gil;
-    PyObject* empty_tuple = PyTuple_New(0);
-    if (!empty_tuple) {
-      mojo::RunLoop::current()->Quit();
-      return;
-    }
-
-    PyObject* result = PyObject_CallObject(callable_, empty_tuple);
-    Py_DECREF(empty_tuple);
-    if (result) {
-      Py_DECREF(result);
-    } else {
-      mojo::RunLoop::current()->Quit();
-      return;
-    }
-  }
-
- private:
-  PyObject* callable_;
-
-  MOJO_DISALLOW_COPY_AND_ASSIGN(PythonClosure);
-};
-
-}  // namespace
-
-namespace mojo {
-
-Closure BuildClosure(PyObject* callable) {
-  if (!PyCallable_Check(callable))
-    return Closure();
-
-  return Closure(
-      static_cast<mojo::Closure::Runnable*>(new PythonClosure(callable)));
-}
-
-}  // namespace mojo