Merge a libxml clang warning fix

Merge a libxml clang warning fix

This fixes the following warning:

/usr/local/google/work/chrome/src/third_party/libxml/src/xpath.c:12269:13: warning: comparison of constant 18 with expression of type 'xmlXPathTypeVal' is always false [-Wtautological-constant-out-of-range-compare]
                        if (type == XML_NAMESPACE_DECL)
                            ~~~~ ^  ~~~~~~~~~~~~~~~~~~

The upstream fix is at http://git.gnome.org/browse/libxml2/commit/?id=713434d2309da469d64b35e163ea6556dadccada

TEST=none
BUG=151927
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=158800

[Nico, 2012-09-26 08:55:07]

lgtm

The upstream patch assumes that out-of-enum assignments don't do anything weird.
type == cur->type might not be true if type is out-of-enum.

But if that's what upstream did, I guess that's what we do :)

[hans, 2012-09-26 09:05:12]

On 2012/09/26 08:55:07, Nico wrote:
> lgtm
> 
> The upstream patch assumes that out-of-enum assignments don't do anything
weird.
> type == cur->type might not be true if type is out-of-enum.
> 
> But if that's what upstream did, I guess that's what we do :)

Yeah, I'm happy enough with that.

[commit-bot: I haz the power, 2012-09-26 09:05:20]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/hans@chromium.org/10984039/1