Add Load method to editor classes and update corresponding headers

src/app/editor/code/assembly_editor.cc

@@ -101,6 +101,10 @@ void AssemblyEditor::Initialize() {
   // Set the language definition
 }
 
+absl::Status AssemblyEditor::Load() {
+  return absl::OkStatus();
+}
+
 void AssemblyEditor::OpenFolder(const std::string& folder_path) {
   current_folder_ = LoadFolder(folder_path);
 }

src/app/editor/code/assembly_editor.h

@@ -34,6 +34,7 @@ class AssemblyEditor : public Editor {
   }
 
   void Initialize() override;
+  absl::Status Load() override;
   void Update(bool &is_loaded);
   void InlineUpdate();