[py] indentation (and highlighting) not working well with type-annotated python

[mtaran-google]

see https://www.python.org/dev/peps/pep-0484/

import typing

class Example(object):

  def method(self, x: typing.List):
    self.x = x

pressing enter at the end of the last or second to last lines changes the indentation to 0, whereas it should indent to 4 in both cases.

Also the type annotation isn't highlighted as a type.

[marijnh]

Attached patch makes the grammar parse things in type position as normal expressions — since they are. Is that okay, or do you want some kind of custom highlighting for such expressions? (This'd require duplicating some stuff and introducing some irregularity in the way things are parsed, so I'm not sure it's a good idea.)

[mtaran-google]

Will show it to users and see what they think :)