Speed up message update handling.

Apparently, checking if something is not None and then calling it is
faster than having an identity function that will just return the
original value untransformed, such as a lambda or doing a str(str) call

discord/message.py

@@ -125,13 +125,16 @@ class Message:
     def __repr__(self):
         return '<Message id={0.id} pinned={0.pinned} author={0.author!r}>'.format(self)
 
-    def _try_patch(self, data, key, transform):
+    def _try_patch(self, data, key, transform=None):
         try:
             value = data[key]
         except KeyError:
             pass
         else:
-            setattr(self, key, transform(value))
+            if transform is None:
+                setattr(self, key, value)
+            else:
+                setattr(self, key, transform(value))
 
     def _add_reaction(self, data):
         emoji = self._state.get_reaction_emoji(data['emoji'])
@@ -171,14 +174,14 @@ class Message:
     def _update(self, channel, data):
         self.channel = channel
         self._edited_timestamp = utils.parse_time(data.get('edited_timestamp'))
-        self._try_patch(data, 'pinned', bool)
-        self._try_patch(data, 'mention_everyone', bool)
-        self._try_patch(data, 'tts', bool)
+        self._try_patch(data, 'pinned')
+        self._try_patch(data, 'mention_everyone')
+        self._try_patch(data, 'tts')
         self._try_patch(data, 'type', lambda x: try_enum(MessageType, x))
-        self._try_patch(data, 'content', str)
-        self._try_patch(data, 'attachments', lambda x: x)
+        self._try_patch(data, 'content')
+        self._try_patch(data, 'attachments')
         self._try_patch(data, 'embeds', lambda x: list(map(Embed.from_data, x)))
-        self._try_patch(data, 'nonce', lambda x: x)
+        self._try_patch(data, 'nonce')
 
         for handler in ('author', 'mentions', 'mention_roles', 'call'):
             try: