ID 321095 - Mari internally selects backdrop nodes when imported and does not deselect

Problem summary
Mari internally selects backdrop nodes when imported and does not deselect

Customer reported version
3.3v1
Customer reported platform
Multiple
Steps to reproduce

1) Launch Mari and open example project
2) Navigate to node graph (views - palettes - node graph)
3) Right click anywhere in the node graph. Select import nodes - navigate to example file
4) Click anywhere in the node graph (this will deselect the imported backdrop/nodes)
5) Hit 'delete' key
Result: Backdrop will be deleted despite not being selected

Workaround
Aside from not importing nodes with a backdrop, n/a

Reproduced by support

This bug has been reproduced in:
3.3v1 - Mac 10.12.3 - Windows 10 - CentOS7
3.2v1 - Mac 10.12.3 - Windows 10 - CentOS7

Unable to reproduce bug in:
Mari 3.3v1 - Mac 10.12.3 - Windows 10 - CentOS7

Earliest version tested
Mari 3.3v1 - Issue no longer occurred 

Expected behaviour
Nothing to happen since node was deselected 

Actual behaviour
Backdrop node was deleted despite not being selected