Steps to reproduce:

1) Download attached project and open in Unity
2) Build and Run "_Complete-Game" scene on a device
3) Observe the enemies, they will not be rendered

Expected result: Using Vulkan Graphics API, objects with Standard(Specular setup) should be rendered on the screen when they're enlighted (check attached image "expected.png")
Actual result: Meshes are not rendered on the screen (check attached image "actual.png")

Reproduced with:
2017.1.3p1, 2017.2.1p4, 2017.3.1p1, 2018.1.0b7

Devices under test:
Reproduced with:
0162 || Razer Phone, OS: 7.1.1, CPU: Qualqomm Snapdragon 835, GPU: Adreno 540
0150 || Google Pixel XL, OS: 8.0, CPU: Snapdragon 821, GPU: Adreno 530

Not reproduced with:
0131 || Huawei P9, OS: 7.0, CPU: HiSilicon Kirin 955, GPU: Mali-T880
0154 || Samsung Galaxy Note 8, OS: 7.1.1, CPU: Samsung Exynos 9 Octa, GPU: Mali-G71
5007 || Nvidia Shield Tablet, OS: 6.0, CPU: nVidia Tegra, GPU: GeForce ULP MP192

Note:
Works as expected using Gles2 and Gles3