Fix crash when user click 'Close' button while Dimension is active.

TaskDlgEditSketch didn't purge the handler first as is doing CmdSketcherLeaveSketch.

src/Mod/Sketcher/Gui/CommandConstraints.cpp

@@ -1061,7 +1061,6 @@ public:
     void deactivated() override
     {
         Gui::Command::abortCommand();
-        //TODO: When user exit sketch edit while tool is activated solve() crashes. solve is needed to refresh the sketch after abortCommand
         Obj->solve();
         sketchgui->draw(false, false); // Redraw
     }

src/Mod/Sketcher/Gui/TaskDlgEditSketch.cpp

@@ -100,6 +100,10 @@ bool TaskDlgEditSketch::reject()
     hGrp->SetBool("ExpandedConstraintsWidget", Constraints->isGroupVisible());
     hGrp->SetBool("ExpandedElementsWidget", Elements->isGroupVisible());
 
+    if (sketchView && sketchView->getSketchMode() != ViewProviderSketch::STATUS_NONE) {
+        sketchView->purgeHandler();
+    }
+
     std::string document = getDocumentName();// needed because resetEdit() deletes this instance
     Gui::Command::doCommand(
         Gui::Command::Gui, "Gui.getDocument('%s').resetEdit()", document.c_str());