merge SPExportController (part of #2789)

Author: dmoagx

Source/SPCSVExporterDelegate.h

@@ -36,7 +36,7 @@
 
 #import <pthread.h>
 
-@interface SPDatabaseStructure (Private_API)
+@interface SPDatabaseStructure ()
 
 - (void)_destroy:(NSNotification *)notification;
 
@@ -469,13 +469,9 @@ - (void)dealloc
 	[super dealloc];
 }
 
-@end
-
 #pragma mark -
 #pragma mark Private API
 
-@implementation SPDatabaseStructure (Private_API)
-
 /**
  * Ensure that processing is completed.
  */