Make ComputedStyleBase internal pointer setters move-only.

Make ComputedStyleBase internal pointer setters move-only.

This patch removes the const ref overload for setters on pointer types.
This means that the internal setter can only be used with an rvalue ref.

This has two consequences:
- We can generate code that works for RefPtrs and std::unique_ptrs
  (since std::unique_ptrs are not copyable, the const ref overload is
   meaningless [*]).
- RefPtrs are passed to internal setters using std::move, which avoids
  ref churn.

[*] Whilst we could make the const ref overload copy the unique_ptr, we
feel that this implicit copying behaviour is bad.

Diff of generated files:
https://gist.github.com/darrnshn/d809ec84cd6418bb1f65ca6dae986630/revisions

This patch does not change behaviour, only the internal API for
ComputedStyleBase.

BUG=628043
Review-Url: https://codereview.chromium.org/2923493003
Cr-Commit-Position: refs/heads/master@{#477111}
Committed: https://chromium.googlesource.com/chromium/src/+/525a0e6f0d79296a4da4f109f7a704ebbcf7f20a

[shend, 2017-06-05 08:09:42]

The CQ bit was checked by shend@chromium.org to run a CQ dry run

[shend, 2017-06-05 08:09:53]

shend@chromium.org changed reviewers:
+ nainar@chromium.org

[shend, 2017-06-05 08:09:54]

Hi Naina, PTAL

[commit-bot: I haz the power, 2017-06-05 08:09:56]

Dry run: 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, 2017-06-05 12:11:41]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-06-05 12:11:43]

Dry run: This issue passed the CQ dry run.

[nainar, 2017-06-05 16:31:44]

lgtm

[shend, 2017-06-05 22:44:30]

The CQ bit was checked by shend@chromium.org

[commit-bot: I haz the power, 2017-06-05 22:45:08]

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, 2017-06-05 22:50:34]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1496702670762670, "parent_rev":
"64dd0e1fab7201713af95e7293e428074ef8536c", "commit_rev":
"525a0e6f0d79296a4da4f109f7a704ebbcf7f20a"}

[commit-bot: I haz the power, 2017-06-05 22:50:45]

Description was changed from

==========
Make ComputedStyleBase internal pointer setters move-only.

This patch removes the const ref overload for setters on pointer types.
This means that the internal setter can only be used with an rvalue ref.

This has two consequences:
- We can generate code that works for RefPtrs and std::unique_ptrs
  (since std::unique_ptrs are not copyable, the const ref overload is
   meaningless [*]).
- RefPtrs are passed to internal setters using std::move, which avoids
  ref churn.

[*] Whilst we could make the const ref overload copy the unique_ptr, we
feel that this implicit copying behaviour is bad.

Diff of generated files:
https://gist.github.com/darrnshn/d809ec84cd6418bb1f65ca6dae986630/revisions

This patch does not change behaviour, only the internal API for
ComputedStyleBase.

BUG=628043
==========

to

==========
Make ComputedStyleBase internal pointer setters move-only.

This patch removes the const ref overload for setters on pointer types.
This means that the internal setter can only be used with an rvalue ref.

This has two consequences:
- We can generate code that works for RefPtrs and std::unique_ptrs
  (since std::unique_ptrs are not copyable, the const ref overload is
   meaningless [*]).
- RefPtrs are passed to internal setters using std::move, which avoids
  ref churn.

[*] Whilst we could make the const ref overload copy the unique_ptr, we
feel that this implicit copying behaviour is bad.

Diff of generated files:
https://gist.github.com/darrnshn/d809ec84cd6418bb1f65ca6dae986630/revisions

This patch does not change behaviour, only the internal API for
ComputedStyleBase.

BUG=628043

Review-Url: https://codereview.chromium.org/2923493003
Cr-Commit-Position: refs/heads/master@{#477111}
Committed:
https://chromium.googlesource.com/chromium/src/+/525a0e6f0d79296a4da4f109f7a7...
==========

[commit-bot: I haz the power, 2017-06-05 22:50:46]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/525a0e6f0d79296a4da4f109f7a7...