When Tilemap Grid size is changed from Inspector then it causes the editor to throw IndexOutOfRangeException, GUI Error, OverflowException continuously, refer attached video.

Steps to repro:
1. Open the attached project
2. Hierarchy > Grid > Tilemap
3. Scene view > Select any Grid
4. Inspector > Grid Selection > Size > input 0, -1, -2 etc OR Resize using mouse dragger.

Actual Result:
Multiple errors are thrown on resizing Grid Size of Tilemap in the Inspector

Expected Result:
Grid Size should resize gracefully

Reproducible on:
2020.2.0a7, 2021.1.0b10, 2020.2.2f1, 2020.2.0a21 with package version 1.0.0

Working fine on:
2020.2.0a20, 2020.1.17f1 with package version 1.0.0

Environment:
Occurring on Windows 10 & Mac 10.15.

Stack trace:
IndexOutOfRangeException: Index was outside the bounds of the array.
UnityEditor.Tilemaps.GridBrushEditor.OnSelectionSceneGUI (UnityEngine.GridLayout gridLayout, UnityEngine.GameObject brushTarget) (at Library/PackageCache/com.unity.2d.tilemap@1.0.0/Editor/GridBrushEditor.cs:364)
UnityEditor.Tilemaps.PaintableSceneViewGrid.CallOnSceneGUI () (at Library/PackageCache/com.unity.2d.tilemap@1.0.0/Editor/PaintableSceneViewGrid.cs:367)
UnityEditor.Tilemaps.PaintableSceneViewGrid.OnSceneGUI (UnityEditor.SceneView sceneView) (at Library/PackageCache/com.unity.2d.tilemap@1.0.0/Editor/PaintableSceneViewGrid.cs:65)
UnityEditor.SceneView.CallOnSceneGUI () (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.SceneView.HandleSelectionAndOnSceneGUI () (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.SceneView.OnGUI () (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.HostView.InvokeOnGUI (UnityEngine.Rect onGUIPosition, UnityEngine.Rect viewRect) (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.DockArea.DrawView (UnityEngine.Rect viewRect, UnityEngine.Rect dockAreaRect) (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.DockArea.OldOnGUI () (at <c2e9ddac9be94c64888ec1c467657510>: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 <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr, Boolean&)

GUI Error: You are pushing more GUIClips than you are popping. Make sure they are balanced.
UnityEngine.GUIUtility:ProcessEvent (int,intptr,bool&)

OverflowException
UnityEditor.Tilemaps.GridBrushEditor.UpdateSelection (UnityEngine.Tilemaps.Tilemap tilemap) (at Library/PackageCache/com.unity.2d.tilemap@1.0.0/Editor/GridBrushEditor.cs:175)
UnityEditor.Tilemaps.GridBrushEditor.OnSelectionSceneGUI (UnityEngine.GridLayout gridLayout, UnityEngine.GameObject brushTarget) (at Library/PackageCache/com.unity.2d.tilemap@1.0.0/Editor/GridBrushEditor.cs:362)
UnityEditor.Tilemaps.PaintableSceneViewGrid.CallOnSceneGUI () (at Library/PackageCache/com.unity.2d.tilemap@1.0.0/Editor/PaintableSceneViewGrid.cs:367)
UnityEditor.Tilemaps.PaintableSceneViewGrid.OnSceneGUI (UnityEditor.SceneView sceneView) (at Library/PackageCache/com.unity.2d.tilemap@1.0.0/Editor/PaintableSceneViewGrid.cs:65)
UnityEditor.SceneView.CallOnSceneGUI () (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.SceneView.HandleSelectionAndOnSceneGUI () (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.SceneView.OnGUI () (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.HostView.InvokeOnGUI (UnityEngine.Rect onGUIPosition, UnityEngine.Rect viewRect) (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.DockArea.DrawView (UnityEngine.Rect viewRect, UnityEngine.Rect dockAreaRect) (at <c2e9ddac9be94c64888ec1c467657510>:0)
UnityEditor.DockArea.OldOnGUI () (at <c2e9ddac9be94c64888ec1c467657510>: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 <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.IMGUIContainer.HandleIMGUIEvent (UnityEngine.Event e, UnityEngine.Matrix4x4 worldTransform, UnityEngine.Rect clippingRect, System.Action onGUIHandler, System.Boolean canAffectFocus) (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.IMGUIContainer.DoIMGUIRepaint () (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.UIR.RenderChainCommand.ExecuteNonDrawMesh (UnityEngine.UIElements.UIR.DrawParams drawParams, System.Single pixelsPerPoint, System.Exception& immediateException) (at <1c96b7a3f7794c85b453037183b01ec4>:0)
Rethrow as ImmediateModeException
UnityEngine.UIElements.UIR.RenderChain.Render () (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.UIRRepaintUpdater.Update () (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.VisualTreeUpdater.UpdateVisualTreePhase (UnityEngine.UIElements.VisualTreeUpdatePhase phase) (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.Panel.UpdateForRepaint () (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.Panel.Repaint (UnityEngine.Event e) (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.UIElementsUtility.DoDispatch (UnityEngine.UIElements.BaseVisualElementPanel panel) (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.UIElementsUtility.UnityEngine.UIElements.IUIElementsUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr, System.Boolean& eventHandled) (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.UIEventRegistration.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr) (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.UIElements.UIEventRegistration+<>c.<.cctor>b__1_2 (System.Int32 i, System.IntPtr ptr) (at <1c96b7a3f7794c85b453037183b01ec4>:0)
UnityEngine.GUIUtility.ProcessEvent (System.Int32 instanceID, System.IntPtr nativeEventPtr, System.Boolean& result) (at <9ff04fda545c4aacb8dab659ad40b2f4>:0)