opengles emulator: fix shader/program info log functions

on some platforms info log length of programs and shaders was
not returned correctly, we now cache the info log for these objects
and calculate info log length intenrally to be both correct and
compliant to the spec and conformance tests.

Change-Id: I017932482ba36f9e2e1858fe372683f7ac3a98ca
5 files changed