The `File.length()` docs state:
> Returns the length of the file denoted by this abstract pathname. The return value is unspecified if this pathname denotes a directory.
On Android, it *seems* to currently have the right behaviour, summing up the size of its children, which made `File.getSizeOfFiles()` double-count the size of some directories.
To avoid this, and be able to control the actual behaviour no matter what future Android versions do, let's count those ourselves.
Jorge Martin Espinosa
8a5c50d2b8