Precompilation: when removing top-level fields and functions, also remove them from the library dic…

runtime/vm/object.h

Index: runtime/vm/object.h
diff --git a/runtime/vm/object.h b/runtime/vm/object.h
index 5ce318c2e35787a2c3880c91c937827d44c7a0b4..2c94c35491311efd264727bee8ba12e8ebcbcbd8 100644
--- a/runtime/vm/object.h
+++ b/runtime/vm/object.h
@@ -3417,6 +3417,7 @@ class Library : public Object {
   void AddClass(const Class& cls) const;
   void AddObject(const Object& obj, const String& name) const;
   void ReplaceObject(const Object& obj, const String& name) const;
+  bool RemoveObject(const Object& obj, const String& name) const;
   RawObject* LookupReExport(const String& name) const;
   RawObject* LookupObjectAllowPrivate(const String& name) const;
   RawObject* LookupLocalObjectAllowPrivate(const String& name) const;