Description of problem:
After a restore without pulp data on Capsule and trying a new Complete Sync from Satellite the following is missing:
The directory modulemd and subdirectories /var/lib/pulp/content/units/modulemd/* are not being created on Capsules.

Version-Release number of selected component (if applicable):
satellite-6.6.0-7.el7sat.noarch
satellite-capsule-6.6.0-7.el7sat.noarch

How reproducible:
100%

Steps to Reproduce:
1. Capsule that lost pulp data or basically `rm -rf /var/lib/pulp/*` while mongodb is still intact
2. Launch a complete sync from Satellite 

Actual results:
Sync fails with:
~~~
PLP0000: [Errno 2] No such file or directory: u'/var/lib/pulp/content/units/modulemd/74/e082fd1a9b0fc5324c19b5c6dae731095e7b6ce102ae3b8b480070f6a06493'
PLP0000: [Errno 2] No such file or directory: u'/var/lib/pulp/content/units/modulemd/52/70496a596fa25e3b94a79ce8b1862811d981d029140fd56d0f1054e7ff58e7'
~~~

Directory structure that gets recreated does not contain modulemd dir

# ls -ltr /var/lib/pulp/content/units
~~~
total 4
drwxr-xr-x.  8 apache apache   66 Nov 20 15:48 yum_repo_metadata_file
drwxr-xr-x. 71 apache apache 4096 Nov 20 15:52 modulemd_defaults
drwxr-xr-x.  7 apache apache   56 Nov 20 18:06 distribution
~~~

Expected results:
Sync to work and all data to be re-synced

Additional info:
All the data is available on the Satellite