Switch to new APIs in samples/translator/translator.cpp

Also, fix a few issuse for ninja build "all" to finish.

BUG=angle:775
TEST=translator.cc compiles OK

Change-Id: I6507e9143882a628a7737dd139efb6d8d358b0db
Reviewed-on: https://chromium-review.googlesource.com/227490
Tested-by: Zhenyao Mo <zmo@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>