### 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
#include "shell/browser/ui/views/inspectable_web_contents_view_views.h"
#include <memory>
#include <utility>
#include "base/strings/utf_string_conversions.h"
#include "shell/browser/ui/inspectable_web_contents.h"
#include "shell/browser/ui/inspectable_web_contents_delegate.h"
#include "shell/browser/ui/inspectable_web_contents_view_delegate.h"
#include "ui/base/models/image_model.h"
#include "ui/views/controls/label.h"
#include "ui/views/controls/webview/webview.h"
#include "ui/views/widget/widget.h"
#include "ui/views/widget/widget_delegate.h"
#include "ui/views/window/client_view.h"
namespace electron {
namespace {
class DevToolsWindowDelegate : public views::ClientView,