Description:
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Suggestion: Don't count 0-bytes files (that comes from <input type="file"> elements that don't have any file specified) towards the max_file_uploads limit. (And don't create a blank temporary file for them to avoid the problems with file-system overload mentioned in CVE-2009-4017.)

Reason for suggestion: That way a small limit for max_file_uploads will cause less website restrictions. For example: I have seen some designs with lists of 40 or 50 rows where every row has a <input type="file"> for the sake of the design of the page. But where typically only one or two files are submitted in a POST because the majority of the <input type="file"> elements has no file specified. Currently all these designs will be limited (to for example 20 rows with the default settings) because even 0-byte files count towards the max_file_uploads limit.

Issues with suggestion: The site will need javascript to control the rare exception where more than for example 20 <input type="file"> has a value before submit. But that should not be a big problem.

Reproduce code:
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HTML POST request with <input type="file"> elements where the value is blank (no file specified) so that $_FILES[#]['size'] is 0 (and $_FILES[#]['tmp_name'] is blank).

Expected result:
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<input type="file"> elements where no file is specified doesn't count towards the max_file_uploads limit

Actual result:
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<input type="file"> elements where no file is specified counts towards the max_file_uploads limit