Introduce a flag to change the new space growth factor

A useful value would be 4, so we get 1, 4, 16MB (instead of the default
value 2 which leads to 1, 2, 4, 8, 16)

BUG=none
R=hpayer@chromium.org
LOG=n

Review URL: https://codereview.chromium.org/753513002

Cr-Commit-Position: refs/heads/master@{#25462}
Slightly improve tests that rely on lazy compilation.

R=rossberg@chromium.org
BUG=v8:3712
LOG=N

Review URL: https://codereview.chromium.org/743843003

Cr-Commit-Position: refs/heads/master@{#25463}
Rip out bzip compression for native sources.

R=vogelheim@chromium.org

Review URL: https://codereview.chromium.org/750543002

Cr-Commit-Position: refs/heads/master@{#25464}
[turbofan] put late ssa deconstruction in register allocator behind a flag

BUG=

Review URL: https://codereview.chromium.org/751543002

Cr-Commit-Position: refs/heads/master@{#25465}
[turbofan]: remove optimization of adds/subs to inc and dec

They generally cause regressions on most modern Intel chips. Replace them with
addl/subl.

Review URL: https://codereview.chromium.org/737153003

Cr-Commit-Position: refs/heads/master@{#25466}
Revert "Remove deprecated ShouldSelfOptimize machinery."

This reverts commit 9da92c1a336e because of performance regressions.

R=danno@chromium.org

Review URL: https://codereview.chromium.org/752613002

Cr-Commit-Position: refs/heads/master@{#25467}
harmony-scoping: Disallow cross-script assignment to const

R=rossberg@chromium.org
BUG=v8:2198
LOG=N

Review URL: https://codereview.chromium.org/745963002

Cr-Commit-Position: refs/heads/master@{#25468}