Speed up GlobalBundleScanningSchemaServiceImpl close
On close, the GlobalBundleScanningSchemaServiceImpl closes the
BundleTracker which untracks all the bundles and notifies the listener
of removed bundles. This results in a call to tryToUpdateSchemaContext
which causes the remaining yang files to be re-parsed to build a new
SchemaContext. To prevent this extra processing on shutdown, I added
a "stopping" flag to elide tryToUpdateSchemaContext the same we do
with the "starting" flag.
Signed-off-by: Tom Pantelis <tpanteli@brocade.com>
Change-Id: I9f7c05277df9bf1ffaec1c699453020312aab203