[turbofan] Improve typing of JSToNumber.

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/786703002

Cr-Commit-Position: refs/heads/master@{#25698}
Make cpplint happy.

TBR=machenbach@chromium.org

Review URL: https://codereview.chromium.org/783913003

Cr-Commit-Position: refs/heads/master@{#25699}
Correct clean up in android perf runner.

BUG=chromium:374740
LOG=n
TEST=python -m unittest run_perf_test
NOTRY=true
TBR=ulan@chromium.org

Review URL: https://codereview.chromium.org/776223003

Cr-Commit-Position: refs/heads/master@{#25700}
Turn on DCHECKs and other debugging code if dcheck_always_on is 1

When compiling with the macro DCHECK_ALWAYS_ON defined, DCHECKs and
supporting code gets compiled and enabled.

This increases test coverage for chromium release buildbots

BUG=v8:3731
R=jkummerow@chromium.org
LOG=y

Review URL: https://codereview.chromium.org/760213005

Cr-Commit-Position: refs/heads/master@{#25701}
Fix compilation with verify heap on in release mode

BUG=none
TBR=rossberg@chromium.org
LOG=n

Review URL: https://codereview.chromium.org/788603002

Cr-Commit-Position: refs/heads/master@{#25702}