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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.cc
.SetMethod("getTitle", &WebContents::GetTitle)
      .SetMethod("isLoading", &WebContents::IsLoading)
      .SetMethod("isLoadingMainFrame", &WebContents::IsLoadingMainFrame)
      .SetMethod("isWaitingForResponse", &WebContents::IsWaitingForResponse)
      .SetMethod("stop", &WebContents::Stop)
      .SetMethod("canGoBack", &WebContents::CanGoBack)
      .SetMethod("goBack", &WebContents::GoBack)
      .SetMethod("canGoForward", &WebContents::CanGoForward)
      .SetMethod("goForward", &WebContents::GoForward)
      .SetMethod("canGoToOffset", &WebContents::CanGoToOffset)
      .SetMethod("goToOffset", &WebContents::GoToOffset)
      .SetMethod("canGoToIndex", &WebContents::CanGoToIndex)
      .SetMethod("goToIndex", &WebContents::GoToIndex)
      .SetMethod("getActiveIndex", &WebContents::GetActiveIndex)
      .SetMethod("clearHistory", &WebContents::ClearHistory)
      .SetMethod("length", &WebContents::GetHistoryLength)
      .SetMethod("isCrashed", &WebContents::IsCrashed)
      .SetMethod("forcefullyCrashRenderer",
                 &WebContents::ForcefullyCrashRenderer)
      .SetMethod("setUserAgent", &WebContents::SetUserAgent)
      .SetMethod("getUserAgent", &WebContents::GetUserAgent)
      .SetMethod("savePage", &WebContents::SavePage)
      .SetMethod("openDevTools", &WebContents::OpenDevTools)
      .SetMethod("closeDevTools", &WebContents::CloseDevTools)
      .SetMethod("isDevToolsOpened", &WebContents::IsDevToolsOpened)
      .SetMethod("isDevToolsFocused", &WebContents::IsDevToolsFocused)
      .SetMethod("enableDeviceEmulation", &WebContents::EnableDeviceEmulation)
      .SetMethod("disableDeviceEmulation", &WebContents::DisableDeviceEmulation)
      .SetMethod("toggleDevTools", &WebContents::ToggleDevTools)
      .SetMethod("inspectElement", &WebContents::InspectElement)