Remove unused fields from the Sessions

Most of the stuff didn't actually need to be saved and only
belong to the MTProtoState which is not a separate class from
the sessions.

telethon/sessions/abstract.py

@@ -1,18 +1,9 @@
 from abc import ABC, abstractmethod
-import time
-import struct
-import os
 
 
 class Session(ABC):
     def __init__(self):
         # Session IDs can be random on every connection
-        self.id = struct.unpack('q', os.urandom(8))[0]
-
-        self._sequence = 0
-        self._last_msg_id = 0
-        self._time_offset = 0
-        self._salt = 0
         self._report_errors = True
         self._flood_sleep_threshold = 60
 
@@ -155,20 +146,6 @@ class Session(ABC):
         """
         raise NotImplementedError
 
-    @property
-    def salt(self):
-        """
-        Returns the current salt used when encrypting messages.
-        """
-        return self._salt
-
-    @salt.setter
-    def salt(self, value):
-        """
-        Updates the salt (integer) used when encrypting messages.
-        """
-        self._salt = value
-
     @property
     def report_errors(self):
         """
@@ -185,21 +162,6 @@ class Session(ABC):
         """
         self._report_errors = value
 
-    @property
-    def time_offset(self):
-        """
-        Time offset (in seconds) to be used
-        in case the local time is incorrect.
-        """
-        return self._time_offset
-
-    @time_offset.setter
-    def time_offset(self, value):
-        """
-        Updates the integer time offset in seconds.
-        """
-        self._time_offset = value
-
     @property
     def flood_sleep_threshold(self):
         """
@@ -214,55 +176,3 @@ class Session(ABC):
         Sets the new time threshold (integer, float or timedelta).
         """
         self._flood_sleep_threshold = value
-
-    @property
-    def sequence(self):
-        """
-        Current sequence number needed to generate messages.
-        """
-        return self._sequence
-
-    @sequence.setter
-    def sequence(self, value):
-        """
-        Updates the sequence number (integer) value.
-        """
-        self._sequence = value
-
-    def get_new_msg_id(self):
-        """
-        Generates a new unique message ID based on the current
-        time (in ms) since epoch, applying a known time offset.
-        """
-        now = time.time() + self._time_offset
-        nanoseconds = int((now - int(now)) * 1e+9)
-        new_msg_id = (int(now) << 32) | (nanoseconds << 2)
-
-        if self._last_msg_id >= new_msg_id:
-            new_msg_id = self._last_msg_id + 4
-
-        self._last_msg_id = new_msg_id
-
-        return new_msg_id
-
-    def update_time_offset(self, correct_msg_id):
-        """
-        Updates the time offset to the correct
-        one given a known valid message ID.
-        """
-        now = int(time.time())
-        correct = correct_msg_id >> 32
-        self._time_offset = correct - now
-        self._last_msg_id = 0
-
-    def generate_sequence(self, content_related):
-        """
-        Generates the next sequence number depending on whether
-        it should be for a content-related query or not.
-        """
-        if content_related:
-            result = self._sequence * 2 + 1
-            self._sequence += 1
-            return result
-        else:
-            return self._sequence * 2