UpdateTestUploadCase->testUploadModule() raises an exception during testing with E_STRICT

chx@veyron:/var/www/7$ php -r 'error_reporting(E_ALL|E_STRICT);function x() { return array();} reset(x());'
PHP Strict standards:  Only variables should be passed by reference in Command line code on line 1
PHP Stack trace:
PHP   1. {main}() Command line code:0
chx@veyron:/var/www/7$ php -r 'error_reporting(E_ALL);function x() { return array();} reset(x());'
chx@veyron:/var/www/7$ 

Confirmed. While the code is the correct fix for this kind of error, we need a comment here to indicate why the --seemingly unncessary-- variable.

• Welcome to core patching
• You forgot the dot from the end of sentence
• I would move the comment one line up
• You can't pass in a reference, Warning: Call-time pass-by-reference has been deprecated would result, the comment needs to be something akin to "We need an extra variable here because reset takes its argument by reference and passing in a constant emits a notice in strict mode"
• dont forget to break at column 80.

Re-rolled to make the comment wrap to 80 characters, to use () after function names for clarity, and to do some minor tweaks to the text to make it read more clearly.

Since it's only nitpicks on the comment, even though it's my patch, I'm just going to RTBC it. ;)

Committed to HEAD. Thanks!