Check command buffer callback queue before VkDevice is destroyed

We only check for signaled events on each queue submit, so the last submission before exit will never be checked.  This change makes sure we release for completed submissions just before the device is destroyed (typically target application exit).  In this case the callbacks are not called.

renderdoc/driver/vulkan/wrappers/vk_device_funcs.cpp

@@ -4660,6 +4660,19 @@ void WrappedVulkan::vkDestroyDevice(VkDevice device, const VkAllocationCallbacks
   SubmitSemaphores();
   FlushQ();
 
+  {
+    SCOPED_LOCK(m_PendingCmdBufferCallbacksLock);
+
+    for(VkPendingSubmissionCompleteCallbacks *pending : m_PendingCmdBufferCallbacks)
+    {
+      const VkResult vkr = ObjDisp(m_Device)->GetEventStatus(Unwrap(m_Device), pending->event);
+      if(vkr == VK_EVENT_SET)
+        pending->Release();
+    }
+
+    m_PendingCmdBufferCallbacks.clear();
+  }
+
   // idle the device as well so that external queues are idle.
   VkResult vkr = ObjDisp(m_Device)->DeviceWaitIdle(Unwrap(m_Device));
   CHECK_VKR(this, vkr);