Rename source_prereqs to inputs in the GN Build file.

Rename source_prereqs to inputs in the GN Build file.

See more information in the gn-dev mailing list:
https://groups.google.com/a/chromium.org/d/msg/gn-dev/j-P5hlvZ13M/4CSw2WworlkJ

Also in
https://chromium.googlesource.com/chromium/src/+/61a6fca4bca5438bf4338184c29fded55e5f240e

BUG=374271
R=machenbach@chromium.org
LOG=N

Committed: https://crrev.com/29684963353e794f3216dfedef7984756535bd0e
Cr-Commit-Position: refs/heads/master@{#26658}

[tfarina, 2015-02-16 11:59:42]

tfarina@chromium.org changed reviewers:
+ machenbach@chromium.org
- jochen@chromium.org

[tfarina, 2015-02-16 11:59:59]

Michael, could you review this to me?

[Michael Achenbach, 2015-02-16 12:03:41]

lgtm

[tfarina, 2015-02-16 12:07:47]

The CQ bit was checked by tfarina@chromium.org

[commit-bot: I haz the power, 2015-02-16 12:08:26]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/917243002/1

[commit-bot: I haz the power, 2015-02-16 12:09:34]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-16 12:09:52]

Patchset 1 (id:??) landed as
https://crrev.com/29684963353e794f3216dfedef7984756535bd0e
Cr-Commit-Position: refs/heads/master@{#26658}