Must use Block_{copy,release} to be GC compliant

Medianno/MAAppController.mm

@@ -17,14 +17,14 @@
       modalForWindow: docWindow
        modalDelegate: self
       didEndSelector: @selector(my_blockSheetDidEnd:returnCode:contextInfo:)
-         contextInfo: [block copy]];
+         contextInfo: Block_copy(block)];
 }
 
 - (void)my_blockSheetDidEnd: (NSWindow *)sheet returnCode: (NSInteger)returnCode contextInfo: (void *)contextInfo
 {
     MASheetBlock block = (MASheetBlock)contextInfo;
     block(returnCode);
-    [block release];
+    Block_release(block);
 }
 
 @end