Add checks to glDrawElementsInstanced, glGetShaderSource am: 6c667b4fb6 am: 0634b5f60b am: 1520532832

Original change: https://googleplex-android-review.googlesource.com/c/device/generic/goldfish-opengl/+/11854593

Change-Id: I1600e4f84a1895c3569b3e4ab32f369963c90db8