Implementing a custom surface shader that uses a different name than "uv_MainTex" for its texture coordinates, causes the Selection Outline feature to stop working.

To reproduce:
1. Open the "Scene" scene in the attached project
2. Switch to Scene View
3. Enable "Selection Outline" in the Gizmos popup
4. Select "Test" Game Object from the Hierarchy

Desired outcome: The Selection Outline is displayed.
Actual result: The Selection Outline is not displayed.

Reproduced with 5.5.4p1, 5.6.0b3, 5.6.2f1, 2017.1.0a1, 2017.1.0f1, 2017.2.0a1, 2017.2.0b1

Update: The issue is marked as 'won't fix' because Unity currently does not have a well-developed mechanism for writing 'tool specific shaders'. Many of the scene view tools have some minor workarounds embedded in them to work for the majority of cases. In the case of scene view selected tool, a custom pixel shader is bound onto the vertex shader that is passed in by the user. If the vertex and pixel shader do not match properly then it leads to odd results.