Lazy-load comment meta on single post pages.

[34268] introduced cache priming for commentmeta, enabled by default. To
ensure performance on single post pages - where commentmeta is most likely
to cause performance issues - we disable up-front cache-priming. Instead, we
prime commentmeta caches for all comments in the loop the first time
`get_comment_meta()` is called on the page.

Props bradt, dd32, wonderboymusic, boonebgorges.
Fixes #16894.
Built from https://develop.svn.wordpress.org/trunk@34270


git-svn-id: http://core.svn.wordpress.org/trunk@34234 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-alpha-34269';
+$wp_version = '4.4-alpha-34270';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.