[3.8] bpo-39031: Include elif keyword when producing lineno/col-offset info for if_stmt (GH-17582)

[miss-islington]

When parsing an "elif" node, lineno and col_offset of the node now point to the "elif" keyword and not to its condition, making it consistent with the "if" node.

https://bugs.python.org/issue39031

Automerge-Triggered-By: @pablogsal
(cherry picked from commit 025a602)

Co-authored-by: Lysandros Nikolaou lisandrosnik@gmail.com

https://bugs.python.org/issue39031

[miss-islington]

@lysnikolaou: Status check is done, and it's a failure ❌ .

[pablogsal]

@brettcannon It seems we have again a similar problem with Travis and pyenv on the maintainance backports (affects both 3.8 and `3.7). Could we make it not required again on these branches? Or there is something we can do to fix it?

[pablogsal]

The error in 3.8 looks like this (for reference):

pyenv: python3.8: command not found
pyenv: python3.8: command not found
pyenv: python3.8: command not found
pyenv: python3.8: command not found
The `python3.8' command exists in these Python versions:
  3.8
  3.8.0

[gvanrossum]

Hm, why are we using pyenv? That seems a dependency reversal.

[brettcannon]

@gvanrossum I think it's because Travis uses it to install specific versions of Python.

@pablogsal done

[miss-islington]

@lysnikolaou: Status check is done, and it's a failure ❌ .

[miss-islington]

@lysnikolaou: Status check is done, and it's a failure ❌ .

[miss-islington]

@lysnikolaou: Status check is done, and it's a failure ❌ .

[miss-islington]

@lysnikolaou: Status check is done, and it's a failure ❌ .

[miss-islington]

@lysnikolaou: Status check is done, and it's a failure ❌ .