Properly close popups for nested progress callbacks (bsc#1223281)

[lslezak]

Problem

• https://bugzilla.suse.com/show_bug.cgi?id=1223281
• After deleting the old repositories a progress popup stays open and blocks the following UI calls

Details

• The problem happens only when the self-update is enabled, with disabled self-update it works fine
• It turned out that with updated libzypp the start and end callbacks are called twice:

modules/PackageCallbacks.rb(ProgressStart):2338 ProgressStart: 992
modules/PackageCallbacks.rb(ProgressStart):2338 ProgressStart: 992
modules/PackageCallbacks.rb(ProgressEnd):2391 ProgressFinish: 992
modules/PackageCallbacks.rb(ProgressEnd):2391 ProgressFinish: 992

• The code is actually prepared for this situation, it counts the nesting level for the start and end calls
• But unfortunately there was a bug when closing the nested callback, it closed only one (the last) popup

Solution

• Properly close the open popup when there are nested callbacks (multiple open popups)

Testing

• Tested manually
• All popups are closed, the workflow properly continues to the next step

[coveralls]

coverage: 41.763%. remained the same
when pulling 7812c96 on close_progress_popups_sp5
into f654b71 on SLE-15-SP5.

[joseivanlopez]

LGTM

[yast-bot]

✔️ Internal Jenkins job #6 successfully finished
✔️ Created IBS submit request #329372