C++: Remove Lexer::{tokenOffset(),tokenLength()}

The necessary data can be retrieved by the resulting Token.

Change-Id: I79afb23183c156240c690beff30bb11dfe943e61
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>

src/libs/3rdparty/cplusplus/Lexer.h

@@ -44,9 +44,6 @@ public:
     inline void operator()(Token *tok)
     { scan(tok); }
 
-    unsigned tokenOffset() const;
-    unsigned tokenLength() const;
-
     bool scanCommentTokens() const;
     void setScanCommentTokens(bool onoff);