### 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

v14.0.0-nightly.20210426

### What operating system are you using?

Windows

### Operating System Version

Windows 10

### What arch are you using?

x64

### Last Known Working Electron version

v14.0.0-nightly.20210413

### Expected Behavior

`BrowserViews` load their `webContents`

### Actual Behavior

BrowserViews will not load `webContents` properly.

### Testcase Gist URL

https://gist.github.com/712a2fde2757736c9dbf6c3e7e0aa18b

### Additional Information

Bisected range: https://github.com/electron/electron/compare/v14.0.0-nightly.20210413...v14.0.0-nightly.20210426
shell/browser/native_browser_view_views.h
#ifndef SHELL_BROWSER_NATIVE_BROWSER_VIEW_VIEWS_H_
#define SHELL_BROWSER_NATIVE_BROWSER_VIEW_VIEWS_H_
#include <memory>
#include <vector>
#include "shell/browser/native_browser_view.h"
#include "third_party/skia/include/core/SkRegion.h"
namespace electron {
class NativeBrowserViewViews : public NativeBrowserView {
 public:
  explicit NativeBrowserViewViews(
      InspectableWebContents* inspectable_web_contents);
  ~NativeBrowserViewViews() override;
  void SetAutoResizeProportions(const gfx::Size& window_size);
  void AutoResize(const gfx::Rect& new_window,
                  int width_delta,
                  int height_delta);
  uint8_t GetAutoResizeFlags() { return auto_resize_flags_; }