Viddler embeds broken by wpautop() due to line breaks

[Viper007Bond]

Viddler contains some new lines too that completely breaks the embed due to silly wpautop(). It shouldn't add <br />'s in the middle of HTML tags, but that's a fix for another day.

Worth putting into 2.9 branch.

[Denis-de-Bernardy]

I'd like to suggest a tiny enhancement to this patch: remove the regexp outright. it's not anchored, and as such serves no purpose beyond slowing things down.

[Denis-de-Bernardy]

if we decide to keep the regexp, it should at least be fixed, e.g.

$domains = array('foo.com', 'bar.com');
$domains = implode('|', array_map('preg_quote', $domains));
if ( preg_match( "#^https?://(?:www\.)?(?:$domains)/#i", ... 

[nacin]

(In [14109]) Strip new lines from Viddler embeds, as we do for Scribd embeds. Avoids conflicts with wpautop. props Viper007Bond. see #12115.

[nacin]

Leaving open for 2.9.x

[nacin]

(In [14249]) Simply search for newlines to strip instead of checking the oEmbed provider. fixes #12115.

[nacin]

Viddler has since fixed this, so no need to commit to the 2.9 branch.

After discussion with Viper in IRC, I've removed the regexp check on the provider, and instead went to a simple strpos to identify any newlines, to slightly improve performance and future-proof any providers that return new lines in the embed code.

[ampt]

Fix strpos paramter order, which should be haystack, needle instead of needle, haystack. See 12115_2.diff attached

[nacin]

(In [14976]) Fix order of params to strpos. props ampt, fixes #12115.