- Electron version: v0.37.5
- Operating system: Any

It would be useful if we can open DevTools choosing all of it's available position: detached, docked right or docked bottom.

The new API could be something like this:
# webContents.openDevTools([options])

Opens the devtools.
- options Object (optional)
  - mode String - ['detached' | 'right' | 'bottom'] . opens DevTools in specified position. Defaults to last used mode.
  - detach Boolean - opens DevTools in a new window (deprecated, use mode: 'detached')

atom/browser/api/atom_api_web_contents.cc
v8::Isolate* isolate, const mate::Dictionary& options) {
  auto handle = mate::CreateHandle(isolate, new WebContents(isolate, options));
  g_wrap_web_contents.Run(handle.ToV8());
  return handle;
}
void ClearWrapWebContents() {
  g_wrap_web_contents.Reset();
}
void SetWrapWebContents(const WrapWebContentsCallback& callback) {
  g_wrap_web_contents = callback;
  
  atom::AtomBrowserMainParts::Get()->RegisterDestructionCallback(
      base::Bind(ClearWrapWebContents));
}
}  
}  
namespace {
void Initialize(v8::Local<v8::Object> exports, v8::Local<v8::Value> unused,
                v8::Local<v8::Context> context, void* priv) {
  v8::Isolate* isolate = context->GetIsolate();
  mate::Dictionary dict(isolate, exports);
  dict.SetMethod("create", &atom::api::WebContents::Create);
  dict.SetMethod("_setWrapWebContents", &atom::api::SetWrapWebContents);
}
}  
NODE_MODULE_CONTEXT_AWARE_BUILTIN(atom_browser_web_contents, Initialize)