Found while investigating #25021

ElectronBrowserMainParts has a periodic timer that is used to trigger GC once a minute even on an idle system. While one wakeup per minute isn't bad, it's also been in there [since 2014](https://github.com/electron/electron/commit/4dd78480846557370dd53789d50e6cb0d6a81bcd) and may or may not still be necessary. It might be worth seeing what happens to memory overhead if this is disabled and/or triggered with a different mechanism.

```c++
  // Start idle gc.
  gc_timer_.Start(
      FROM_HERE, base::TimeDelta::FromMinutes(1),
      base::Bind(&v8::Isolate::LowMemoryNotification,
                 base::Unretained(js_env_->isolate())));
```


shell/browser/electron_browser_main_parts.cc
base::FilePath path;
  if (base::PathService::Get(DIR_APP_DATA, &path))
    return;
  std::unique_ptr<base::Environment> env(base::Environment::Create());
  path = base::nix::GetXDGDirectory(env.get(), base::nix::kXdgConfigHomeEnvVar,
                                    base::nix::kDotConfigDir);
  base::PathService::Override(DIR_APP_DATA, path);
}
void UpdateDarkThemeSetting() {
  float bg = color_utils::GetRelativeLuminance(gtk::GetBgColor("GtkLabel"));
  float fg = color_utils::GetRelativeLuminance(gtk::GetFgColor("GtkLabel"));
  bool is_dark = fg > bg;
  
  
  ui::NativeTheme::GetInstanceForNativeUi()->set_use_dark_colors(is_dark);
  
  ui::NativeTheme::GetInstanceForWeb()->set_use_dark_colors(is_dark);
}
#endif
}  
#if defined(OS_LINUX)
class DarkThemeObserver : public ui::NativeThemeObserver {