HackStudio: Make debugger support shared libraries

Author: https://github.com/itamar8910
Commit: 94db04fc12
Pull-request: https://github.com/SerenityOS/serenity/pull/4852
Reviewed-by: https://github.com/ADKaster
Reviewed-by: https://github.com/awesomekling

DevTools/HackStudio/Debugger/VariablesModel.cpp

@@ -184,7 +184,10 @@ void VariablesModel::update()
 
 RefPtr<VariablesModel> VariablesModel::create(const PtraceRegisters& regs)
 {
-    auto variables = Debugger::the().session()->debug_info().get_variables_in_current_scope(regs);
+    auto lib = Debugger::the().session()->library_at(regs.eip);
+    if (!lib)
+        return nullptr;
+    auto variables = lib->debug_info->get_variables_in_current_scope(regs);
     return adopt(*new VariablesModel(move(variables), regs));
 }