store: lazily get file size on demand for the fncache case
We don't have the information in the first place, so we can avoid querying the
file system inconditionnaly for use case we don't needs it.
This change requires the StoreFile class to be passed a vfs to retrieve the
file_size if needed.
In the non-fncache case, we already have the information from file system
walking, so we keep it and use it.
{
// 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)
}