How to reproduce:
1. Open project "crash976749.zip"
2. Open "planet" scene
3. Main Camera -> "Custom Light Renderer (Script)" enabled = true
4. Switch to scene window
5. Observe the crash (reopen the project if the crash doesn't occur the first time)

Reproduced with: 5.6.0a6, 5.6.5f1, 2017.1.2p4, 2017.0.2f3, 2017.2.1p1, 2017.3.0f3, 2018.1.0b1
Not reproducible with 5.5, 5.6.0a5 (either the project is incompatible with these versions or random crashes occur for different reasons)

Note: Editor crashes only when "Scene" tab is open
Note: With 2017.x versions, sometimes "PrepareRenderNodesQueueToMainThread" is on the top of the stack trace (instead of "ExecuteRenderQueue")
Note: With 5.6 versions "RenderManager::AddCameraProjector" is on the top of the stack trace

========== OUTPUTING STACK TRACE ==================

0x0000000140CAB268 (Unity) ExecuteRenderQueue
0x0000000140CAB34C (Unity) ExecuteRenderQueueJob
0x0000000141076B73 (Unity) JobQueue::Exec
0x0000000141075B69 (Unity) JobQueue::Steal
0x0000000141075F27 (Unity) JobQueue::ExecuteJobFromQueue
0x0000000141076E64 (Unity) JobQueue::ProcessJobs
0x0000000141076F4E (Unity) JobQueue::WorkLoop
0x00000001415ACDCC (Unity) Thread::RunThreadWrapper
0x00007FFB84EA1FE4 (KERNEL32) BaseThreadInitThunk
0x00007FFB8566EF91 (ntdll) RtlUserThreadStart

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

Fixed in: 2018.2.0a3 (a0fbd73019b1)