Steps to reproduce:
1. Create a new 2D Unity project
2. Create -> 2D Object -> Sprite Shape in Hierarchy
3. Click Edit Spline on Sprite Shape Controller in Inspector
4. Enable Cache Geometry
5. Disable Edit Spline on Sprite Shape Controller

Expected result: No errors are thrown
Actual result: ArgumentException error is thrown

Reproduced with: 2D SpriteShape 3.0.15 (2019.4.22f1), 5.1.1 (2020.3.0f1),
Didn't reproduce with: 2D SpriteShape 3.0.14 (2019.4.22f1)

Full error:
ArgumentException: Slice start + length (6) range must be <= slice.Length (1)
Unity.Collections.NativeSlice`1[T]..ctor (Unity.Collections.NativeSlice`1[T] slice, System.Int32 start, System.Int32 length) (at /Users/bokken/buildslave/unity/build/Runtime/Export/NativeArray/NativeSlice.cs:72)
UnityEngine.U2D.SpriteShapeCopyUtility`1[T].Copy (T[] dst, Unity.Collections.NativeSlice`1[T] src, System.Int32 length) (at Library/PackageCache/com.unity.2d.spriteshape@3.0.15/Runtime/SplineUtility.cs:81)
SpriteShapeGeometryCache.UpdateGeometryCache () (at Library/PackageCache/com.unity.2d.spriteshape@3.0.15/Runtime/SpriteShapeGeometryCache.cs:108)
UnityEditor.U2D.SpriteShapeUpdateCache.UpdateCache (UnityEngine.Object[] targets) (at Library/PackageCache/com.unity.2d.spriteshape@3.0.15/Editor/SpriteShapeControllerEditor.cs:597)
UnityEditor.U2D.SpriteShapeControllerEditor.OnInspectorGUI () (at Library/PackageCache/com.unity.2d.spriteshape@3.0.15/Editor/SpriteShapeControllerEditor.cs:354)
UnityEditor.UIElements.InspectorElement+<>c__DisplayClass58_0.<CreateIMGUIInspectorFromEditor>b__0 () (at /Users/bokken/buildslave/unity/build/Editor/Mono/Inspector/InspectorElement.cs:527)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr) (at /Users/bokken/buildslave/unity/build/Modules/IMGUI/GUIUtility.cs:197)