Description:
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When building a phar with addFile, it is possible to list the folders with scandir or opendir. 
When building the same phar with buildFromIterator, some of the folders in the phar archive can't be read. I get the following error : 

PHP Warning:  scandir(phar:///tmp/iterator.phar/folder/sub): failed to open dir: operation failed in phar:///tmp/iterator.phar/test on line 3

Test script:
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The attached gist creates a few files, and build 2 phar with the same structure.
The one created with iterator fails, while the other one is OK, displaying a folder listing.

Expected result:
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Building phar with archives allows for all folder listing.

Actual result:
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error when using scandir, opendir in the phar.