When the "Look Dev" window is docked and "Scriptable Render Pipeline" Asset is set to "None" from the Graphics Settings, then it causes the editor to throw ArgumentException, refer attached video.

Steps to repro:
1. Create a new project with HDRP Template
2. Window > Render Pipeline > Look Dev
3. Docked the Look Dev window
3. Edit > Project Settings > Graphics
4. Scriptable Render Pipeline Settings > None

Actual Result:
ArgumentException is thrown when Look Dev window is docked and SRP Asset set to None

Expected Result:
"Scriptable Render Pipeline" Asset is set to "None" without any errors when the "Look Dev" window is docked

Reproducible in:
2020.2.0a18, 2020.1.0b16, 2019.4.3f1, 2019.3.15f1 with Package Version 9.0.0-preview.33, 8.1.0, 8.0.1, 7.4.1, 7.3.1.

Environment:
Occurring on Windows 10 & macOS 10.15

Stack Trace:
ArgumentException: Getting control 0's position in a group with only 0 controls when doing repaint
Aborting
UnityEngine.GUILayoutGroup.GetNext () (at <9e3b197786024cdcb531b292c5998102>:0)
UnityEngine.GUILayoutUtility.BeginLayoutGroup (UnityEngine.GUIStyle style, UnityEngine.GUILayoutOption[] options, System.Type layoutType) (at <9e3b197786024cdcb531b292c5998102>:0)
UnityEngine.GUILayout.BeginHorizontal (UnityEngine.GUIContent content, UnityEngine.GUIStyle style, UnityEngine.GUILayoutOption[] options) (at <9e3b197786024cdcb531b292c5998102>:0)
UnityEngine.GUILayout.BeginHorizontal (UnityEngine.GUIStyle style, UnityEngine.GUILayoutOption[] options) (at <9e3b197786024cdcb531b292c5998102>:0)
UnityEditor.GameView.DoToolbarGUI () (at <833199c02ee84e91a3a7100aef51217f>:0)
UnityEditor.GameView.OnGUI () (at <833199c02ee84e91a3a7100aef51217f>:0)
UnityEditor.HostView.InvokeOnGUI (UnityEngine.Rect onGUIPosition, UnityEngine.Rect viewRect) (at <833199c02ee84e91a3a7100aef51217f>:0)
UnityEditor.DockArea.DrawView (UnityEngine.Rect viewRect, UnityEngine.Rect dockAreaRect) (at <833199c02ee84e91a3a7100aef51217f>:0)
UnityEditor.DockArea.OldOnGUI () (at <833199c02ee84e91a3a7100aef51217f>:0)
UnityEngine.UIElements.IMGUIContainer.DoOnGUI (UnityEngine.Event evt, UnityEngine.Matrix4x4 parentTransform, UnityEngine.Rect clippingRect, System.Boolean isComputingLayout, UnityEngine.Rect layoutSize, System.Action onGUIHandler, System.Boolean canAffectFocus) (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.IMGUIContainer.HandleIMGUIEvent (UnityEngine.Event e, UnityEngine.Matrix4x4 worldTransform, UnityEngine.Rect clippingRect, System.Action onGUIHandler, System.Boolean canAffectFocus) (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.IMGUIContainer.DoIMGUIRepaint () (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.UIR.RenderChainCommand.ExecuteNonDrawMesh (UnityEngine.UIElements.UIR.DrawParams drawParams, System.Single pixelsPerPoint, System.Exception& immediateException) (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
Rethrow as ImmediateModeException
UnityEngine.UIElements.UIR.RenderChain.Render () (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.UIRRepaintUpdater.Update () (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.VisualTreeUpdater.UpdateVisualTreePhase (UnityEngine.UIElements.VisualTreeUpdatePhase phase) (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.Panel.UpdateForRepaint () (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.Panel.Repaint (UnityEngine.Event e) (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.UIElementsUtility.DoDispatch (UnityEngine.UIElements.BaseVisualElementPanel panel) (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.UIElementsUtility.UnityEngine.UIElements.IUIElementsUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr, System.Boolean& eventHandled) (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.UIEventRegistration.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr) (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.UIElements.UIEventRegistration+<>c.<.cctor>b__1_2 (System.Int32 i, System.IntPtr ptr) (at <434515d9f4bb4f26bab9aa61f75e4922>:0)
UnityEngine.GUIUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr, System.Boolean& result) (at <9e3b197786024cdcb531b292c5998102>:0)