Reproduction steps:
1. Open the attached project.
2. Play the 'Instancing' scene.

Actual behavior:
The shader will not compile with error - "Unexpected identifier "StructuredBuffer". Expected one of: typedef const void inline uniform nointerpolation extern shared static volatile row_major column_major struct or a user-defined type"

Note:
Actual/expected behavior screenshots attached.

Regression introduced in:
2017.3

Reproduced with:
2017.3.0b3
2017.3.0a1

Not reproducible with:
2017.2.0f3