HackStudio: Show a backtrace in the debug information tab

Author: https://github.com/itamar8910
Commit: 1fb62df02a
Pull-request: https://github.com/SerenityOS/serenity/pull/2157
Reviewed-by: https://github.com/awesomekling

Libraries/LibDebug/DebugInfo.h

@@ -93,6 +93,8 @@ public:
         }
     }
 
+    String name_of_containing_function(u32 address) const;
+
 private:
     void prepare_variable_scopes();
     void prepare_lines();