To reproduce:
1. Open my attached project
2. In Hierarchy window, select TileSprite game object
3. In Inspector window, try changing size parameters of Sprite Renderer component

Expected: Box Collider 2D changes according to the size of the sprite
Actual: Box Collider 2D changes according to the size of single slice of the sprite (see picture attached, SpriteSlice.png)

Reproduced in: 5.6.1p2, 5.6.1p3, 2017.1.0b9, 2017.2.0a3
Not reproduced in: 5.6.1p1
Regression starts in: 5.6.1p2

Note: tiling is not available in earlier versions of Unity
Note: Box Collider 2D is using the bounds of only one slice of the sprite instead of all of it