### Preflight Checklist

- [X] I have read the [Contributing Guidelines](https://github.com/electron/electron/blob/master/CONTRIBUTING.md) for this project.
- [X] I agree to follow the [Code of Conduct](https://github.com/electron/electron/blob/master/CODE_OF_CONDUCT.md) that this project adheres to.
- [X] I have searched the [issue tracker](https://www.github.com/electron/electron/issues) for a feature request that matches the one I want to file, without success.

### Electron Version

12.0.5

### What operating system are you using?

Ubuntu

### Operating System Version

Ubuntu 21.04 x86_64 5.11.0-16-generic

### What arch are you using?

x64

### Last Known Working Electron version

_No response_

### Expected Behavior

All clicking inside the developer tool works well and not being interrupted by dragging the electron app.

### Actual Behavior

When I click the `option` and `close` tool inside the developer tool, it drags the electron app.

https://user-images.githubusercontent.com/61906684/118137437-666fd600-b42f-11eb-9443-ea1ebad1d0ec.mp4



### Testcase Gist URL

_No response_

### Additional Information

This bug only occurs if the dock position is on the left.
shell/browser/ui/views/inspectable_web_contents_view_views.cc
return this;
}
views::View* InspectableWebContentsViewViews::GetWebView() {
  return contents_web_view_;
}
void InspectableWebContentsViewViews::ShowDevTools(bool activate) {
  if (devtools_visible_)
    return;
  devtools_visible_ = true;
  if (devtools_window_) {
    devtools_window_web_view_->SetWebContents(
        inspectable_web_contents_->GetDevToolsWebContents());
    devtools_window_->SetBounds(
        inspectable_web_contents()->GetDevToolsBounds());
    if (activate) {
      devtools_window_->Show();
    } else {
      devtools_window_->ShowInactive();
    }
  } else {
    devtools_web_view_->SetVisible(true);
    devtools_web_view_->SetWebContents(
        inspectable_web_contents_->GetDevToolsWebContents());
    devtools_web_view_->RequestFocus();
    Layout();
  }
}
void InspectableWebContentsViewViews::CloseDevTools() {