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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/ui/inspectable_web_contents.cc
base::Value dict(base::Value::Type::DICTIONARY);
  dict.SetKey("x", base::Value(bounds.x()));
  dict.SetKey("y", base::Value(bounds.y()));
  dict.SetKey("width", base::Value(bounds.width()));
  dict.SetKey("height", base::Value(bounds.height()));
  return dict;
}
gfx::Rect DictionaryToRect(const base::Value* dict) {
  const base::Value* found = dict->FindKey("x");
  int x = found ? found->GetInt() : 0;
  found = dict->FindKey("y");
  int y = found ? found->GetInt() : 0;
  found = dict->FindKey("width");
  int width = found ? found->GetInt() : 800;
  found = dict->FindKey("height");
  int height = found ? found->GetInt() : 600;
  return gfx::Rect(x, y, width, height);
}
bool IsPointInRect(const gfx::Point& point, const gfx::Rect& rect) {