This is the renderer code for GLES1 that delivers basic vertex
attributes, matrices, and allows texturing for unit 0 only (more units
mean implementing the multitexturing pipeline).

+ Sample
+ Update test expectations for GLES1 conformance tests

BUG=angleproject:2554
BUG=angleproject:2306

Change-Id: I398edc764f982fbfc4c5e0f9d6bfef1e91aec47c
Reviewed-on: https://chromium-review.googlesource.com/1057356Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Lingfeng Yang <lfy@google.com>