Revert of Improve performance of GeometryMapper cache.

Revert of Improve performance of GeometryMapper cache. (patchset #39 id:690001 of https://codereview.chromium.org/2729243002/ )

Reason for revert:
Breaks msan:
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20Trusty%20MSAN/builds/781

Original issue's description:
> Improve performance of GeometryMapper cache.
> 
> 1. Store clips and transforms in vectors attached to the clip and transform nodes.
> This avoids all hash map lookups. Invalidation uses a global cache generation id
> (currently we don't support anything other than global invalidation of the
> GeometryMapper caches).
> 
> 2. Return clips and transforms by reference, to avoid copying.
> 
> #1 is expected to be a good optimization because we almost always compute clips
> and transforms relative to the same ancestor, so the vectors are short and hash
> lookups are reduced.
> 
> BUG=692614
> CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
> 
> Review-Url: https://codereview.chromium.org/2729243002
> Cr-Commit-Position: refs/heads/master@{#455571}
> Committed: https://chromium.googlesource.com/chromium/src/+/ee72c4b5d2fd1e4882bddca66e0f89fe8784a7fc

TBR=pdr@chromium.org,wangxianzhu@chromium.org,chrishtr@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=692614
Review-Url: https://codereview.chromium.org/2738113003
Cr-Commit-Position: refs/heads/master@{#455706}
Committed: https://chromium.googlesource.com/chromium/src/+/b0ef4258b2832480c9086fac69210b3338a38198

[Michael Achenbach, 2017-03-09 09:12:47]

The CQ bit was checked by machenbach@chromium.org

[Michael Achenbach, 2017-03-09 09:12:47]

Created Revert of Improve performance of GeometryMapper cache.

[commit-bot: I haz the power, 2017-03-09 09:13:08]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-03-09 09:13:55]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1489050767371600, "parent_rev":
"72f3c9b47d08185135faeab172c1130f34f1ca66", "commit_rev":
"b0ef4258b2832480c9086fac69210b3338a38198"}

[commit-bot: I haz the power, 2017-03-09 09:14:56]

Description was changed from

==========
Revert of Improve performance of GeometryMapper cache. (patchset #39 id:690001
of https://codereview.chromium.org/2729243002/ )

Reason for revert:
Breaks msan:
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20Trusty...

Original issue's description:
> Improve performance of GeometryMapper cache.
> 
> 1. Store clips and transforms in vectors attached to the clip and transform
nodes.
> This avoids all hash map lookups. Invalidation uses a global cache generation
id
> (currently we don't support anything other than global invalidation of the
> GeometryMapper caches).
> 
> 2. Return clips and transforms by reference, to avoid copying.
> 
> #1 is expected to be a good optimization because we almost always compute
clips
> and transforms relative to the same ancestor, so the vectors are short and
hash
> lookups are reduced.
> 
> BUG=692614
>
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
> 
> Review-Url: https://codereview.chromium.org/2729243002
> Cr-Commit-Position: refs/heads/master@{#455571}
> Committed:
https://chromium.googlesource.com/chromium/src/+/ee72c4b5d2fd1e4882bddca66e0f...

TBR=pdr@chromium.org,wangxianzhu@chromium.org,chrishtr@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=692614
==========

to

==========
Revert of Improve performance of GeometryMapper cache. (patchset #39 id:690001
of https://codereview.chromium.org/2729243002/ )

Reason for revert:
Breaks msan:
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20Trusty...

Original issue's description:
> Improve performance of GeometryMapper cache.
> 
> 1. Store clips and transforms in vectors attached to the clip and transform
nodes.
> This avoids all hash map lookups. Invalidation uses a global cache generation
id
> (currently we don't support anything other than global invalidation of the
> GeometryMapper caches).
> 
> 2. Return clips and transforms by reference, to avoid copying.
> 
> #1 is expected to be a good optimization because we almost always compute
clips
> and transforms relative to the same ancestor, so the vectors are short and
hash
> lookups are reduced.
> 
> BUG=692614
>
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
> 
> Review-Url: https://codereview.chromium.org/2729243002
> Cr-Commit-Position: refs/heads/master@{#455571}
> Committed:
https://chromium.googlesource.com/chromium/src/+/ee72c4b5d2fd1e4882bddca66e0f...

TBR=pdr@chromium.org,wangxianzhu@chromium.org,chrishtr@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=692614

Review-Url: https://codereview.chromium.org/2738113003
Cr-Commit-Position: refs/heads/master@{#455706}
Committed:
https://chromium.googlesource.com/chromium/src/+/b0ef4258b2832480c9086fac6921...
==========

[commit-bot: I haz the power, 2017-03-09 09:14:57]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/b0ef4258b2832480c9086fac6921...