logic: Fixed source files indexed multiple times when in multiple source groups

src/lib/project/Project.h

@@ -47,7 +47,11 @@ public: // todo: make private again
 private:
 	bool requestIndex(bool forceRefresh, bool needsFullRefresh);
 
-	void buildIndex(const std::set<FilePath>& filesToClean, bool fullRefresh, bool preprocessorOnly);
+	void buildIndex(
+		const std::set<FilePath>& filesToIndex,
+		const std::set<FilePath>& filesToClean,
+		bool fullRefresh,
+		bool preprocessorOnly);
 
 	bool hasCxxSourceGroup() const;