Try over-retaining some void* casts to keep the objects around 'till they are handled

Note that these currently aren't balanced.

Author: rowanj

PBGitIndexController.m

@@ -216,7 +216,7 @@ - (void) discardChangesForFiles:(NSArray *)files force:(BOOL)force
         [alert beginSheetModalForWindow:[[commitController view] window]
                           modalDelegate:self
                          didEndSelector:@selector(discardChangesForFilesAlertDidEnd:returnCode:contextInfo:)
-                            contextInfo:(__bridge void*)files];
+                            contextInfo:(__bridge_retained void*)files];
 	} else {
         [commitController.index discardChangesForFiles:files];
     }

PBRefController.m

@@ -89,7 +89,7 @@ - (void)showConfirmPushRefSheet:(PBGitRef *)ref remote:(PBGitRef *)remoteRef
 	[alert beginSheetModalForWindow:[historyController.repository.windowController window]
 					  modalDelegate:self
 					 didEndSelector:@selector(confirmPushRefSheetDidEnd:returnCode:contextInfo:)
-						contextInfo:(__bridge void*)info];
+						contextInfo:(__bridge_retained void*)info];
 }
 
 - (void)confirmPushRefSheetDidEnd:(NSAlert *)sheet returnCode:(int)returnCode contextInfo:(void *)contextInfo
@@ -270,7 +270,7 @@ - (void)showDeleteRefSheet:(PBRefMenuItem *)sender
 	[alert beginSheetModalForWindow:[historyController.repository.windowController window]
 					  modalDelegate:self
 					 didEndSelector:@selector(deleteRefSheetDidEnd:returnCode:contextInfo:)
-						contextInfo:(__bridge void*)ref];
+						contextInfo:(__bridge_retained void*)ref];
 }
 
 - (void)deleteRefSheetDidEnd:(NSAlert *)sheet returnCode:(int)returnCode contextInfo:(void  *)contextInfo
@@ -426,7 +426,7 @@ - (BOOL)tableView:(NSTableView *)aTableView
 	[alert beginSheetModalForWindow:[historyController.repository.windowController window]
 					  modalDelegate:self
 					 didEndSelector:@selector(acceptDropInfoAlertDidEnd:returnCode:contextInfo:)
-						contextInfo:(__bridge void*)dropInfo];
+						contextInfo:(__bridge_retained void*)dropInfo];
 
 	return YES;
 }

PBWebChangesController.m

@@ -119,7 +119,7 @@ - (void)discardHunk:(NSString *)hunk altKey:(BOOL)altKey
 		[alert beginSheetModalForWindow:[[controller view] window]
                           modalDelegate:self
                          didEndSelector:@selector(discardHunkAlertDidEnd:returnCode:contextInfo:)
-                            contextInfo:(__bridge void*)hunk];
+                            contextInfo:(__bridge_retained void*)hunk];
 	} else {
         [self discardHunk:hunk];
     }