Return the correct server response for the 'message' response field from the server.
Previously this would use the generic message corresponding to the response code, which isn't always accurate. Since we're already parsing the headers, we can simply return that directly (This also has the benefit that it's the same code for both Streams and Curl header handling).
Fixes #28919

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git-svn-id: http://core.svn.wordpress.org/trunk@29611 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Always cast the 'code' server response to an int, this provides consistency between both of the HTTP transports.
Previously cURL would return an int and Streams a numeric string.
Fixes #28887

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git-svn-id: http://core.svn.wordpress.org/trunk@29612 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Correctly handle url's containing url's in WP_HTTP::make_absolute_url().
A valid relative URL could be mistaken for an absolute url if it contained a :// in any position of the url.
Fixes #28001

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git-svn-id: http://core.svn.wordpress.org/trunk@29613 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Correctly support Schemeless URLs in WP_HTTP::make_absolute_url() by respecting the 'host' field if present in the relative url.
Fixes #29886

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