If trap handlers cannot be installed, we printed two lines to stdout
and stderr, both not terminated by a newline. This CL adds a newline to
one output and uses the FATAL macro for the other, highlighting the
error better and showing the location where it happens.

R=eholk@chromium.org

Bug: v8:7570
Change-Id: Ic24f48f92b87528e0fd5889badf2c90d765e451a
Reviewed-on: https://chromium-review.googlesource.com/1047606Reviewed-by: Eric Holk <eholk@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53043}