Fix reordering of build steps in the clean list

 * Fix reordering of build steps in the clean list of steps.
 * Make the code more robust and avoid removing and inserting
   the item.
 * Update code for the build steps list too for reasons of symetry.

Reviewed-by: dt

src/plugins/projectexplorer/buildconfiguration.cpp

@@ -143,8 +143,10 @@ void BuildConfiguration::removeBuildStep(int position)
 
 void BuildConfiguration::moveBuildStepUp(int position)
 {
-    BuildStep *bs = m_buildSteps.takeAt(position);
-    m_buildSteps.insert(position - 1, bs);
+    if (position <= 0 || m_buildSteps.size() <= 1)
+        return;
+    m_buildSteps.swap(position - 1, position);
+
 }
 
 QList<BuildStep *> BuildConfiguration::cleanSteps() const
@@ -165,8 +167,9 @@ void BuildConfiguration::removeCleanStep(int position)
 
 void BuildConfiguration::moveCleanStepUp(int position)
 {
-    BuildStep *cs = m_cleanSteps.takeAt(position);
-    m_cleanSteps.insert(position, cs);
+    if (position <= 0 || m_cleanSteps.size() <= 1)
+        return;
+    m_cleanSteps.swap(position - 1, position);
 }
 
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