Remove unnecessary MemberHash<> templates.

Remove unnecessary MemberHash<> templates.

Directly define the hash traits of all heap reference template types
(Member<T> - or Persistent<T>-derived) in terms of MemberHash<T>,
and avoid introducing ad-hoc templates for these.

Add missing (CrossThread)WeakPersistent<T> hash traits also.

R=
BUG=

Committed: https://crrev.com/95d55a4f8ca7f2088cd31cba4b0cba2643e94f84
Cr-Commit-Position: refs/heads/master@{#400155}

[sof, 2016-06-16 12:32:29]

sigbjornf@opera.com changed reviewers:
+ oilpan-reviews@chromium.org

[sof, 2016-06-16 12:32:29]

please take a look.

[haraken, 2016-06-16 14:39:33]

LGTM

[sof, 2016-06-16 15:04:13]

The CQ bit was checked by sigbjornf@opera.com

[commit-bot: I haz the power, 2016-06-16 15:04:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2067223005/1

[commit-bot: I haz the power, 2016-06-16 15:07:54]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-06-16 15:07:55]

CQ bit was unchecked

[commit-bot: I haz the power, 2016-06-16 15:09:08]

Description was changed from

==========
Remove unnecessary MemberHash<> templates.

Directly define the hash traits of all heap reference template types
(Member<T> - or Persistent<T>-derived) in terms of MemberHash<T>,
and avoid introducing ad-hoc templates for these.

Add missing (CrossThread)WeakPersistent<T> hash traits also.

R=
BUG=
==========

to

==========
Remove unnecessary MemberHash<> templates.

Directly define the hash traits of all heap reference template types
(Member<T> - or Persistent<T>-derived) in terms of MemberHash<T>,
and avoid introducing ad-hoc templates for these.

Add missing (CrossThread)WeakPersistent<T> hash traits also.

R=
BUG=

Committed: https://crrev.com/95d55a4f8ca7f2088cd31cba4b0cba2643e94f84
Cr-Commit-Position: refs/heads/master@{#400155}
==========

[commit-bot: I haz the power, 2016-06-16 15:09:09]

Patchset 1 (id:??) landed as
https://crrev.com/95d55a4f8ca7f2088cd31cba4b0cba2643e94f84
Cr-Commit-Position: refs/heads/master@{#400155}