- Unite translator with translator_lib
- Remove flags and defines for shared library exports

BUG=angleproject:1596

Change-Id: Icd145a4b79e2472766a2b56017bb0f36f244482e
Reviewed-on: https://chromium-review.googlesource.com/410261Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Yuly Novikov <ynovikov@chromium.org>