Remove implicit conversion from scoped_refptr to T* in tools/gn

Remove implicit conversion from scoped_refptr to T* in tools/gn

This patch was generated by running the rewrite_scoped_refptr clang tool
on a ChromeOS build.

BUG=110610
Committed: https://crrev.com/b66e11dac00cfeb4ff097ead712dae5acfe05986
Cr-Commit-Position: refs/heads/master@{#294632}

[dcheng, 2014-09-10 21:09:36]

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

[dcheng, 2014-09-10 21:09:36]

I'm not sure why this showed up when I ran the tool over a CrOS build. I guess
that someone is still working with an older checkout on a non-Linux platform?

[brettw, 2014-09-12 17:13:55]

lgtm

[dcheng, 2014-09-12 17:15:39]

The CQ bit was checked by dcheng@chromium.org

[commit-bot: I haz the power, 2014-09-12 17:16:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/555163004/1

[commit-bot: I haz the power, 2014-09-12 19:30:41]

Committed patchset #1 (id:1) as 026e4e88ca42b97b333556931166ab1c9d834735

[commit-bot: I haz the power, 2014-09-12 19:35:46]

Patchset 1 (id:??) landed as
https://crrev.com/b66e11dac00cfeb4ff097ead712dae5acfe05986
Cr-Commit-Position: refs/heads/master@{#294632}