Fix classes that have too many virtuals for inline constructors.

net/tools/balsa/balsa_frame.h

Index: net/tools/balsa/balsa_frame.h
diff --git a/net/tools/balsa/balsa_frame.h b/net/tools/balsa/balsa_frame.h
index 27f27ea53d2cf4121339f342049ed557511ffcef..bece9ab1a2014d7d38e6eeca27e9b4a7280a70ff 100644
--- a/net/tools/balsa/balsa_frame.h
+++ b/net/tools/balsa/balsa_frame.h
@@ -200,6 +200,10 @@ class BalsaFrame {
 
  private:
   class DoNothingBalsaVisitor : public BalsaVisitorInterface {
+   public:
+    DoNothingBalsaVisitor();
+
+   private:
     void ProcessBodyInput(const char* input, size_t size) override {}
     void ProcessBodyData(const char* input, size_t size) override {}
     void ProcessHeaderInput(const char* input, size_t size) override {}
@@ -258,4 +262,3 @@ class BalsaFrame {
 }  // namespace net
 
 #endif  // NET_TOOLS_BALSA_BALSA_FRAME_H_
-