LightApp: Fix compilation without PV3DViewer

[jschueller]

When compiling a minimal gui with -DSALOME_USE_PV3DVIEWER=OFF it errors with:

/home/devel/src/gui/src/LightApp/LightApp_Application.cxx: In member function ‘virtual SUIT_ViewManager* LightApp_Application::createViewManager(const QString&, bool)’:
/home/devel/src/gui/src/LightApp/LightApp_Application.cxx:2154:19: error: expected type-specifier before ‘PV3DViewer_ViewManager’
 2154 |     viewMgr = new PV3DViewer_ViewManager( activeStudy(), desktop() );
      |                   ^~~~~~~~~~~~~~~~~~~~~~
/home/devel/src/gui/src/LightApp/LightApp_Application.cxx:2155:5: error: ‘PV3DViewer_ViewModel’ was not declared in this scope; did you mean ‘PyViewer_Viewer’?
 2155 |     PV3DViewer_ViewModel* vm = dynamic_cast<PV3DViewer_ViewModel*>( viewMgr->getViewModel() );
      |     ^~~~~~~~~~~~~~~~~~~~
      |     PyViewer_Viewer
/home/devel/src/gui/src/LightApp/LightApp_Application.cxx:2155:27: error: ‘vm’ was not declared in this scope; did you mean ‘tm’?
 2155 |     PV3DViewer_ViewModel* vm = dynamic_cast<PV3DViewer_ViewModel*>( viewMgr->getViewModel() )

seems the second condition is just not guarded by DISABLE_SALOMEOBJECT
compilation goes through after this patch
cc @nitawa

[nitawa]

@martin-bernhard : this basically is related to GUI PR2997 which was sadly left on the side (apologize for that).

[nitawa]

@jschueller : Thanks for the fix, let's integrate it then and check it on our side.

[nitawa]

If not mistaken, as reported in the past, this breaks GEOM compilation. Let's check this again.

[jschueller]

yes but that's an independent task to be done in geom right ?

[nitawa]

yes. you can check the pull request I mentioned, since you seem to have an account on tuleap. regards.