pgAdmin 4 commit: Do not validate the model unnecessarily (when closing

Do not validate the model unnecessarily (when closing).
Clear the cache of a node, whenever an object has been removed of that
kind, it will allow us to fetch the latest list.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=b2b6d443b5205ec3ce52bdfd273630a8a8a3f555

Modified Files
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web/pgadmin/browser/static/js/datamodel.js       | 4 ++--
web/pgadmin/browser/templates/browser/js/node.js | 4 ++++
2 files changed, 6 insertions(+), 2 deletions(-)