Use getattr for better performance

  __getattribute__ is called everytime any attribute is accessed on
  request. It catches AttributeErrors in order to proxy to the
  underlying request. getattr is called, by python, whenever an
  attribute is missing and has a much lower overhead.

Author: chrisseto

rest_framework/request.py

@@ -346,11 +346,24 @@ def _not_authenticated(self):
         else:
             self.auth = None
 
-    def __getattribute__(self, attr):
+    def __getattr__(self, attr):
         """
         If an attribute does not exist on this instance, then we also attempt
         to proxy it to the underlying HttpRequest object.
         """
+        try:
+            return getattr(self._request, attr)
+        except AttributeError:
+            # Call the original implementation of getattribute
+            # So the correct attribute error will get raised
+            self.__getattr_trace__(attr)
+
+    def __getattr_trace__(self, attr):
+        """
+        The original implementation of __getattribute__ which
+        generates correct tracebacks
+        See #2108 and #2530
+        """
         try:
             return super(Request, self).__getattribute__(attr)
         except AttributeError: