use unique_ptr to document ownership (PNS::LINE_PLACER)

pcbnew/router/pns_line_placer.cpp

@@ -59,8 +59,6 @@ LINE_PLACER::LINE_PLACER( ROUTER* aRouter ) :
 
 LINE_PLACER::~LINE_PLACER()
 {
-    if( m_shove )
-        delete m_shove;
 }
 
 
@@ -796,14 +794,11 @@ void LINE_PLACER::initPlacement()
     m_currentNode = m_world;
     m_currentMode = Settings().Mode();
 
-    if( m_shove )
-        delete m_shove;
-
-    m_shove = NULL;
+    m_shove.reset();
 
     if( m_currentMode == RM_Shove || m_currentMode == RM_Smart )
     {
-        m_shove = new SHOVE( m_world->Branch(), Router() );
+        m_shove.reset( new SHOVE( m_world->Branch(), Router() ) );
     }
 }
 

pcbnew/router/pns_line_placer.h

@@ -368,7 +368,7 @@ private:
     VECTOR2I m_p_start;
 
     ///> The shove engine
-    SHOVE* m_shove;
+    std::unique_ptr< SHOVE > m_shove;
 
     ///> Current world state
     NODE* m_currentNode;