Avoid a notice for an undefined $checksums variable when updating from pre-3.7 to post-3.7.

props GaryJ.
fixes #25689 for trunk.

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git-svn-id: http://core.svn.wordpress.org/trunk@25878 1a063a9b-81f0-0310-95a4-ce76da25c4cd
3.7 regression: Fix the width of captioned images inserted into the visual editor.

Pulls some arithmetic outside of some string concatenation to avoid a nasty uglify.js regression: https://github.com/mishoo/UglifyJS2/pull/330.

props LucP.
fixes #25700 for trunk.

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git-svn-id: http://core.svn.wordpress.org/trunk@25880 1a063a9b-81f0-0310-95a4-ce76da25c4cd
3.7 regression from [25119]: Have in_category() return false when the first argument is empty.

Adds unit tests.

props ericlewis.
fixes #25706 for trunk.

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git-svn-id: http://core.svn.wordpress.org/trunk@25882 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In update_option(), call the update_option hook before the DB update.

Reverses a regression from [25664].

props calin.
fixes #25705 for trunk.

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git-svn-id: http://core.svn.wordpress.org/trunk@25884 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Have get_current_user_id() return 0 when pluggable.php is not yet included (which brings the ability to set or get the current user).

fixes #25690 for trunk.

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git-svn-id: http://core.svn.wordpress.org/trunk@25888 1a063a9b-81f0-0310-95a4-ce76da25c4cd
In search stopwords filtering, suppress possible PHP warnings when PCRE lacks UTF-8 support.

see #25709.

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git-svn-id: http://core.svn.wordpress.org/trunk@25891 1a063a9b-81f0-0310-95a4-ce76da25c4cd