Don't use Mojo to get the primary account in identity_get_auth_token_function.cc

identity_get_auth_token_function.cc uses a mix of C++ and Mojo code.
This CL ports GetPrimaryAccountInfo() to C++.

Bug: 913853
Change-Id: I8fe68deacec443d6a93fd9ec13543b5cdef881bf
Reviewed-on: https://chromium-review.googlesource.com/c/1458298
Commit-Queue: Henrique Ferreiro <hferreiro@igalia.com>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: David Roger <droger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#632564}
2 files changed