Closing a Project with Post Processing effects when 'Verify Saving Assets' is enabled leads to the Editor crashing after the save assets window pops up.
Refer to the attached video.

Steps to Reproduce:
1. Create a New Project
2. Window > Package Manager > Post Processing 2.3.0 > Install
3. Assets > Create > Post Processing Profile
4. Hierarchy > Right-click > Create Empty
5. Gameobject > Inspector > Add Component > Post-process Volume
6. Add PP Profile asset to PP Volume component of Gameobject
7. Mark the PP component as Global
8. Add any effect
9. Edit > Preferences > General > Verify Saving Assets > Enable
10. Disable the added effect on the PP component
11. Close the Editor using top right "X" icon
12. Choose "Don't Save" in both pop-up windows when warned about unsaved changes

Actual Result:
Editor crashes on closing the project after the save assets pop-up

Expected Result:
Editor closes gracefully after the save assets pop-up

Occurring on:
2020.2.0a1, 2020.1.0a26, 2020.1.0a22

Working Fine on:
2020.1.0a21, 2019.3.3f1

Environment:
Only Windows 10

========== OUTPUTTING STACK TRACE ==================

0x00007FF6EFF5E1CB (Unity) PersistentManager::ReadObject
0x00007FF6EE824AE5 (Unity) PPtr<MonoBehaviour>::operator MonoBehaviour * __ptr64
0x00007FF6F126388E (Unity) ContainerWindow::GetMonoContainerWindowData
0x00007FF6F125CB21 (Unity) ContainerWindow::CleanupContainerWindow
0x00007FF6F125D1FB (Unity) ContainerWindow::ContainerWndProc
0x00007FFDBF547446 (USER32) DispatchMessageW
0x00007FFDBF54716C (USER32) DispatchMessageW
0x00007FFDBF550A23 (USER32) EnumChildWindows
0x00007FFDC1BE34A4 (ntdll) KiUserCallbackDispatcher
0x00007FFDBDDE23E4 (win32u) NtUserDestroyWindow
0x00007FF6F125D137 (Unity) ContainerWindow::ContainerWndProc
0x00007FFDBF547446 (USER32) DispatchMessageW
0x00007FFDBF54716C (USER32) DispatchMessageW
0x00007FFDBF550A23 (USER32) EnumChildWindows
0x00007FFDC1BE34A4 (ntdll) KiUserCallbackDispatcher
0x00007FFDBDDE1184 (win32u) NtUserMessageCall
0x00007FFDBF544740 (USER32) GetWindowTextW
0x00007FFDBF5442B2 (USER32) GetWindowTextW
0x00007FFDBBE4EB62 (uxtheme) GetThemeAppProperties
0x00007FFDBBE4EC42 (uxtheme) GetThemeAppProperties
0x00007FFDBBE48776 (uxtheme) Ordinal119
0x00007FFDBBE47791 (uxtheme) Ordinal119
0x00007FFDBF5444B4 (USER32) GetWindowTextW
0x00007FF6F125DAFE (Unity) ContainerWindow::ContainerWndProc
0x00007FFDBF547446 (USER32) DispatchMessageW
0x00007FFDBF54716C (USER32) DispatchMessageW
0x00007FFDBF550A23 (USER32) EnumChildWindows
0x00007FFDC1BE34A4 (ntdll) KiUserCallbackDispatcher
0x00007FFDBDDE1184 (win32u) NtUserMessageCall
0x00007FFDBF544740 (USER32) GetWindowTextW
0x00007FFDBF5442B2 (USER32) GetWindowTextW
0x00007FFDBBE4EB62 (uxtheme) GetThemeAppProperties
0x00007FFDBBE4ED04 (uxtheme) GetThemeAppProperties
0x00007FFDBBE48776 (uxtheme) Ordinal119
0x00007FFDBBE47791 (uxtheme) Ordinal119
0x00007FFDBF5444B4 (USER32) GetWindowTextW
0x00007FF6F125DAFE (Unity) ContainerWindow::ContainerWndProc
0x00007FFDBF547446 (USER32) DispatchMessageW
0x00007FFDBF546F62 (USER32) DispatchMessageW
0x00007FF6F1266FF6 (Unity) MainMessageLoop
0x00007FF6F127082E (Unity) WinMain
0x00007FF6F2E91B56 (Unity) __scrt_common_main_seh
0x00007FFDBF1D7974 (KERNEL32) BaseThreadInitThunk
0x00007FFDC1BAA261 (ntdll) RtlUserThreadStart

========== END OF STACKTRACE ===========