Fix Chromium build with DPLOG_IF
Fix Chromium build with DPLOG_IF

Chromium has many build configurations. One important configuration
that’s not tested by its commit queue doesn’t use |condition| in
DLOG_IF(severity, condition) or any of the D*LOG_IF macros, resulting in
errors such as

…/handler/handler_main.cc:166:7: error: unused variable 'rv' [-Werror,-Wunused-variable]
  int rv = sigaction(sig, &sa, nullptr);
      ^

BUG=chromium:695314

Change-Id: I09a57379e8276b5ffa7f8f81706581a802d76809
Reviewed-on: https://chromium-review.googlesource.com/446559
Reviewed-by: Robert Sesek <f55ad94e336f3a28322d0a25d280221ea9daf7a3@chromium.org>

atom/crashpad,chromium/crashpad,atom/crashpad,chromium/crashpad,chromium/crashpad,atom/crashpad