Fix T44040: Blender crashes when nodes are muted

It was actually an old issue with wrong conversion happening for muted
nodes, which wasn't visible before memory optimization commit.

This is to be backported to the final release.

source/blender/compositor/intern/COM_NodeOperationBuilder.cpp

@@ -101,12 +101,12 @@ void NodeOperationBuilder::convertToOperations(ExecutionSystem *system)
 		}
 	}
 	
+	resolve_proxies();
+	
 	add_datatype_conversions();
 	
 	add_operation_input_constants();
 	
-	resolve_proxies();
-	
 	determineResolutions();
 	
 	/* surround complex ops with read/write buffer */