THRIFT-2320 Program level doctext does not get attached by parser

Patch: Craig Peterson & Jens Geyer
diff --git a/compiler/cpp/src/main.h b/compiler/cpp/src/main.h
index 46ad835..d554970 100644
--- a/compiler/cpp/src/main.h
+++ b/compiler/cpp/src/main.h
@@ -103,6 +103,12 @@
 char* clean_up_doctext(char* doctext);
 
 /**
+ * We are sure the program doctext candidate is really the program doctext.
+ */
+void declare_valid_program_doctext();
+
+
+/**
  * Flex utilities
  */