Add support for generating the QtCreator projects from GN.

tools/gn/import_manager.h

Index: tools/gn/import_manager.h
diff --git a/tools/gn/import_manager.h b/tools/gn/import_manager.h
index 78bb613322af8d8ce867ae6ee7be149d51f1c6f8..f371520df8ce60d3ffad8e3b7e191e65f3d8f9b2 100644
--- a/tools/gn/import_manager.h
+++ b/tools/gn/import_manager.h
@@ -7,6 +7,7 @@
 
 #include <map>
 #include <memory>
+#include <vector>
 
 #include "base/macros.h"
 #include "base/synchronization/lock.h"
@@ -30,6 +31,8 @@ class ImportManager {
                 Scope* scope,
                 Err* err);
 
+  std::vector<SourceFile> GetImportedFiles() const;
+
  private:
   struct ImportInfo;