Fixed issues reported by Coverity.

common/tool/context_menu.cpp

@@ -182,7 +182,15 @@ void CONTEXT_MENU::Clear()
 
 void CONTEXT_MENU::UpdateAll()
 {
-    m_update_handler();
+    try
+    {
+        m_update_handler();
+    }
+    catch( std::exception& e )
+    {
+        std::cerr << "CONTEXT_MENU error running update handler: " << e.what() << std::endl;
+    }
+
     updateHotKeys();
 
     runOnSubmenus( boost::bind( &CONTEXT_MENU::UpdateAll, _1 ) );

pcbnew/tools/picker_tool.cpp

@@ -54,7 +54,17 @@ int PICKER_TOOL::Main( const TOOL_EVENT& aEvent )
             m_picked = controls->GetCursorPosition();
 
             if( m_clickHandler )
-                getNext = (*m_clickHandler)( *m_picked );
+            {
+                try
+                {
+                    getNext = (*m_clickHandler)( *m_picked );
+                }
+                catch( std::exception& e )
+                {
+                    std::cerr << "PICKER_TOOL click handler error: " << e.what() << std::endl;
+                    break;
+                }
+            }
 
             if( !getNext )
                 break;

pcbnew/tools/selection_conditions.cpp

@@ -136,7 +136,7 @@ bool SELECTION_CONDITIONS::sameNetFunc( const SELECTION& aSelection, bool aAllow
             if( netcode == NETINFO_LIST::UNCONNECTED && !aAllowUnconnected )
                 return false;
         }
-        else if( netcode != item->GetNetCode() )
+        else if( netcode != current_netcode )
         {
             return false;
         }