PD: use Base::StateLocker to simplify handling of blockUpdate and make it exception-safe

src/Mod/PartDesign/Gui/TaskRevolutionParameters.cpp

@@ -27,6 +27,7 @@
 #include <App/DocumentObject.h>
 #include <App/Origin.h>
 #include <Base/Console.h>
+#include <Base/Tools.h>
 #include <Gui/Application.h>
 #include <Gui/CommandT.h>
 #include <Gui/Selection.h>
@@ -103,8 +104,7 @@ TaskRevolutionParameters::TaskRevolutionParameters(PartDesignGui::ViewProvider*
 
 void TaskRevolutionParameters::fillAxisCombo(bool forceRefill)
 {
-    bool oldVal_blockUpdate = blockUpdate;
-    blockUpdate = true;
+    Base::StateLocker lock(blockUpdate, true);
 
     if (axesInList.empty())
         forceRefill = true;//not filled yet, full refill
@@ -169,8 +169,6 @@ void TaskRevolutionParameters::fillAxisCombo(bool forceRefill)
     //highlight current.
     if (indexOfCurrent != -1)
         ui->axis->setCurrentIndex(indexOfCurrent);
-
-    blockUpdate = oldVal_blockUpdate;
 }
 
 void TaskRevolutionParameters::addAxisToCombo(App::DocumentObject* linkObj,
@@ -201,11 +199,8 @@ void TaskRevolutionParameters::updateUI()
 {
     if (blockUpdate)
         return;
-    blockUpdate = true;
-
+    Base::StateLocker lock(blockUpdate, true);
     fillAxisCombo();
-
-    blockUpdate = false;
 }
 
 void TaskRevolutionParameters::onSelectionChanged(const Gui::SelectionChanges& msg)