pgAdmin 4 commit: 1) Edit cellEditing function,in some cases grid obje

1) Edit cellEditing function, in some cases grid object is undefined.
2) Modify SubNodeCollectionControl, so that user can pass custom backgrid row.
3) Handling of visible parameter in SubNodeCollectionControl.
4) Customise title and delete message for Delete Cell.
5) Added Backgrid.Extension.Select2DepCell and moved Backgrid.Extension.StringDepCell from user management to
backgrid.pgadmin.js.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=c98b64fd828b5030f724a001b8cb8b99cfcee179

Modified Files
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web/pgadmin/static/js/backform.pgadmin.js          | 28 ++++++---
web/pgadmin/static/js/backgrid.pgadmin.js          | 71 +++++++++++++++++++---
.../user_management/js/user_management.js          | 31 +---------
3 files changed, 84 insertions(+), 46 deletions(-)