GitLab

Target.exposeDevToolsProtocol implementation was attaching the
same client to multiple agent hosts. In fact, we assume there's
a single client per session.

R=dgozman

Change-Id: I780abc7d86612cef977999e6f6319f00722cee1a
Reviewed-on: https://chromium-review.googlesource.com/1221726
Commit-Queue: Andrey Lushnikov <lushnikov@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#591420}