Remove high promotion mode

Remove high promotion mode

High promotion mode limits new space size in the case where many objects (high
rate) are promoted.  The result is frequent scavenger runs with low pause times. The
approach conflicts with pretenuring which requires a larger new space size to
collect enough feedback to be usable.

Ultimately the goal is to have pretenuring catch allocation sites that have high
promotion rates.

Revert "Bring back high promotion mode to shrink young generation size when scavenging latency is high."

This reverts commit 37be1d5e9e0a34abe6ba1612b9825e59f28a52d8.

Revert "GC. Delay/avoid entering high promotion mode"

This reverts commit a5221d0779d0839055c764b88f412a0793d959b3.

BUG=chromium:499507, chromium:506910
LOG=n

Committed: https://crrev.com/40bb3a58a0a2c4fb85bad668e2489977df449277
Cr-Commit-Position: refs/heads/master@{#29983}

[Michael Lippautz, 2015-07-21 07:58:07]

mlippautz@chromium.org changed reviewers:
+ hpayer@chromium.org

[Michael Lippautz, 2015-07-21 08:42:35]

Patchset #2 (id:20001) has been deleted

[Hannes Payer (out of office), 2015-08-03 16:59:02]

This does not work well with pretenuring. We are going to remove it, again. LGTM

[Hannes Payer (out of office), 2015-08-03 16:59:35]

The CQ bit was checked by hpayer@chromium.org

[commit-bot: I haz the power, 2015-08-03 16:59:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1247723003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1247723003/1

[commit-bot: I haz the power, 2015-08-03 17:29:36]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-08-03 17:29:58]

Patchset 1 (id:??) landed as
https://crrev.com/40bb3a58a0a2c4fb85bad668e2489977df449277
Cr-Commit-Position: refs/heads/master@{#29983}