Enable template checking for the clang plugin everywhere.

Enable template checking for the clang plugin everywhere.

This enables the plugin to check templated classes for the following
things:
- Refcounted types have private destructors.
- WeakPtrFactory members are the last members

BUG=441916
Committed: https://crrev.com/33761b490534b36a0da1bd413bd29bd2edb3ac77
Cr-Commit-Position: refs/heads/master@{#359258}

[dcheng, 2015-11-11 23:33:57]

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

[dcheng, 2015-11-11 23:33:57]

Trying to close out some old TODOs, assuming this compiles.

It looks like https://llvm.org/bugs/show_bug.cgi?id=21942 is fixed as well, so
after this, I should be able to repurpose this flag and increase the scope to
cover virtual method specifiers as well.

[Nico, 2015-11-11 23:36:51]

lgtm if it builds

a follow-up can now remove the flag from the plugin, right?

[dcheng, 2015-11-12 03:46:56]

On 2015/11/11 at 23:36:51, thakis wrote:
> lgtm if it builds
> 
> a follow-up can now remove the flag from the plugin, right?

I was thinking about repurposing the flag for fixing virtual specifiers, but if
removing it and adding a new flag would make the clang roll easier, I can do
that instead.

Also, it looks like it's passing the bots (with the exception of the win clang
x64 debug bot which has been broken by a skia change), so going to CQ it.

[dcheng, 2015-11-12 03:47:36]

The CQ bit was checked by dcheng@chromium.org

[commit-bot: I haz the power, 2015-11-12 03:48:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1438053002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1438053002/20001

[commit-bot: I haz the power, 2015-11-12 04:24:46]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-11-12 20:04:50]

Patchset 2 (id:??) landed as
https://crrev.com/33761b490534b36a0da1bd413bd29bd2edb3ac77
Cr-Commit-Position: refs/heads/master@{#359258}