gn: Use .obj extension for pch objects on Windows.

gn: Use .obj extension for pch objects on Windows.

Fixes a cosmetic regression from https://codereview.chromium.org/1292983004

BUG=603902
Committed: https://crrev.com/c065bd83a55626de81db52aca9bf88dbb425e904
Cr-Commit-Position: refs/heads/master@{#387893}

[Nico, 2016-04-17 04:48:41]

thakis@chromium.org changed reviewers:
+ brettw@chromium.org

[brettw, 2016-04-18 05:26:12]

lgtm

[Nico, 2016-04-18 11:28:57]

The CQ bit was checked by thakis@chromium.org

[commit-bot: I haz the power, 2016-04-18 11:29:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1893933002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1893933002/1

[commit-bot: I haz the power, 2016-04-18 12:07:59]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-04-18 12:09:45]

Description was changed from

==========
gn: Use .obj extension for pch objects on Windows.

Fixes a cosmetic regression from https://codereview.chromium.org/1292983004

BUG=603902
==========

to

==========
gn: Use .obj extension for pch objects on Windows.

Fixes a cosmetic regression from https://codereview.chromium.org/1292983004

BUG=603902

Committed: https://crrev.com/c065bd83a55626de81db52aca9bf88dbb425e904
Cr-Commit-Position: refs/heads/master@{#387893}
==========

[commit-bot: I haz the power, 2016-04-18 12:09:46]

Patchset 1 (id:??) landed as
https://crrev.com/c065bd83a55626de81db52aca9bf88dbb425e904
Cr-Commit-Position: refs/heads/master@{#387893}