filemerge: move removal of `.orig` extension on temp file close to context
The place where the `.orig` extension is removed in `_maketempfiles()`
doesn't make it clear that it's the backup path, which is why we have
a comment in the code explaining it. Let's instead move it out of the
function and close to where we get it from `backup.path()`, so that
becomes clear.
Differential Revision: https://phab.mercurial-scm.org/D12190
{
// Enforcing
"eqeqeq" : true, // true: Require triple equals (===) for comparison
"forin" : true, // true: Require filtering for..in loops with obj.hasOwnProperty()
"freeze" : true, // true: prohibits overwriting prototypes of native objects such as Array, Date etc.
"nonbsp" : true, // true: Prohibit "non-breaking whitespace" characters.
"undef" : true, // true: Require all non-global variables to be declared (prevents global leaks)
// Environments
"browser" : true // Web Browser (window, document, etc)
}