BASE: Ignore -NSDocumentRevisionDebugMode command line argument on OS X

This is automatically added by Xcode when not toggling off the
"Allow debugging when using document Versions Browser". Since
this is on by default, and to avoid everybody having to google it,
I have decided to just ignore it on OS X.

base/commandLine.cpp

@@ -386,9 +386,15 @@ Common::String parseCommandLine(Common::StringMap &settings, int argc, const cha
 		} else {
 			// On MacOS X prior to 10.9 the OS is sometimes adding a -psn_X_XXXXXX argument (where X are digits)
 			// to pass the process serial number. We need to ignore it to avoid an error.
+			// When using XCode it also adds -NSDocumentRevisionsDebugMode YES argument if XCode option
+			// "Allow debugging when using document Versions Browser" is on (which is the default).
 #ifdef MACOSX
 			if (strncmp(s, "-psn_", 5) == 0)
 				continue;
+			if (strcmp(s, "-NSDocumentRevisionsDebugMode") == 0) {
+				++i; // Also skip the YES that follows
+				continue;
+			}
 #endif
 
 			bool isLongCmd = (s[0] == '-' && s[1] == '-');