Rewrite end tags to match start tags in html-sanitizer.

When the tagPolicy provided to html-sanitizer modifes the tagName,
rewrite matching end tags as well as start tags.

Add tests for the tagPolicy-using interface.

@r5170

[metaweta, 2012-11-07 21:20:23]

https://codereview.appspot.com/6810096/diff/1/tests/com/google/caja/plugin/ht...
File tests/com/google/caja/plugin/html-sanitizer-test.js (right):

https://codereview.appspot.com/6810096/diff/1/tests/com/google/caja/plugin/ht...
tests/com/google/caja/plugin/html-sanitizer-test.js:350: checkT('<p>a<xpx
r="1">b</xpx>c</p>',
Are you closing optional tags before doing the replacement or afterwards?  The
original text is equivalent to
   <p>a</p><p>b</p>c,
so I'd expect the output to be
   <p>a</p><xpx r="1">b</xpx>c
instead.

[kpreid2, 2012-11-29 22:37:33]

When the tagPolicy provided to html-sanitizer modifes the tagName,
rewrite matching end tags as well as start tags.

Add tests for the tagPolicy-using interface.

[kpreid2, 2012-11-29 22:53:32]

https://codereview.appspot.com/6810096/diff/1/tests/com/google/caja/plugin/ht...
File tests/com/google/caja/plugin/html-sanitizer-test.js (right):

https://codereview.appspot.com/6810096/diff/1/tests/com/google/caja/plugin/ht...
tests/com/google/caja/plugin/html-sanitizer-test.js:350: checkT('<p>a<xpx
r="1">b</xpx>c</p>',
On 2012/11/07 21:20:23, metaweta wrote:
> Are you closing optional tags before doing the replacement or 
> afterwards?  The original text is equivalent to
>    <p>a</p><p>b</p>c,
> so I'd expect the output to be
>    <p>a</p><xpx r="1">b</xpx>c
> instead.

This test case was incoherent. New snapshot has a different test case and
generates the proper output from this type of scenario.

[metaweta, 2012-11-30 02:06:12]

lgtm