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### Issue Details
Electron Version: All Version
Operating System: macOS 10.15.3
Last Known Working Electron version: Never

### Bug
The color picker in devtools does not work.
In devtools if you want to change the colors of the CSS code. When you click on a color a color picker is supposed to appear but it does not appear.

### Screenshots
<img width="1013" alt="Capture d’écran 2020-09-07 à 11 42 44" src="https://user-images.githubusercontent.com/70572698/92374841-988ea280-f100-11ea-96be-afc93f6dd645.png">

shell/browser/api/electron_api_web_contents.h
content::RenderFrameHost* sender,
                      electron::mojom::ElectronBrowser::InvokeCallback callback,
                      Args&&... args) {
    DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
    v8::Isolate* isolate = JavascriptEnvironment::GetIsolate();
    v8::HandleScope handle_scope(isolate);
    v8::Local<v8::Object> wrapper;
    if (!GetWrapper(isolate).ToLocal(&wrapper))
      return false;
    v8::Local<v8::Object> event = gin_helper::internal::CreateNativeEvent(
        isolate, wrapper, sender, std::move(callback));
    return EmitCustomEvent(name, event, std::forward<Args>(args)...);
  }
  WebContents* embedder() { return embedder_; }
#if BUILDFLAG(ENABLE_ELECTRON_EXTENSIONS)
  extensions::ScriptExecutor* script_executor() {
    return script_executor_.get();
  }
#endif
  
  void SetOwnerWindow(NativeWindow* owner_window);
  void SetOwnerWindow(content::WebContents* web_contents,
                      NativeWindow* owner_window);
  
  content::WebContents* GetWebContents() const;
  
  content::WebContents* GetDevToolsWebContents() const;
  InspectableWebContents* inspectable_web_contents() const {