C++ editor: Remove scanning/caching of includes

With the completion now in a separate thread this should
no longer be necessary.

Reviewed-by: Roberto Raggi

src/plugins/cpptools/cppcompletionassist.h

@@ -97,6 +97,7 @@ private:
 
     void completeObjCMsgSend(CPlusPlus::ClassOrNamespace *binding, bool staticClassAccess);
     bool completeInclude(const QTextCursor &cursor);
+    void completeInclude(const QString &realPath, const QStringList &suffixes);
     void completePreprocessor();
     bool completeConstructorOrFunction(const QList<CPlusPlus::LookupItem> &results,
                                        int endOfExpression,