[debug] always add debug slot for statements.

[debug] always add debug slot for statements.

Previously we would elide debug slots if the statement position it
belongs to has just already been written. The motivation is that since
we should only break once per statement, we can elide debug slots that
has the same statement position as the previous debug slot.

This is an unnecessary optimization, since the debugger has yet another
check against breaking twice at the same statement at runtime, in
Debug::Break.

This optimization can also be wrong, if there is control flow involved,
for example if we can jump to the elided debug slot without executing
the previous debug slot.

CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel
R=jgruber@chromium.org

Committed: https://crrev.com/9611a4d24b19a79a78094dbb7e9373b58a71eda4
Cr-Commit-Position: refs/heads/master@{#37107}

[jgruber, 2016-06-20 12:02:02]

lgtm

[Yang, 2016-06-20 12:53:58]

The CQ bit was checked by yangguo@chromium.org

[commit-bot: I haz the power, 2016-06-20 12:54:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2080173002/1

[commit-bot: I haz the power, 2016-06-20 14:14:36]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-06-20 14:15:22]

Description was changed from

==========
[debug] always add debug slot for statements.

Previously we would elide debug slots if the statement position it
belongs to has just already been written. The motivation is that since
we should only break once per statement, we can elide debug slots that
has the same statement position as the previous debug slot.

This is an unnecessary optimization, since the debugger has yet another
check against breaking twice at the same statement at runtime, in
Debug::Break.

This optimization can also be wrong, if there is control flow involved,
for example if we can jump to the elided debug slot without executing
the previous debug slot.

CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel
R=jgruber@chromium.org
==========

to

==========
[debug] always add debug slot for statements.

Previously we would elide debug slots if the statement position it
belongs to has just already been written. The motivation is that since
we should only break once per statement, we can elide debug slots that
has the same statement position as the previous debug slot.

This is an unnecessary optimization, since the debugger has yet another
check against breaking twice at the same statement at runtime, in
Debug::Break.

This optimization can also be wrong, if there is control flow involved,
for example if we can jump to the elided debug slot without executing
the previous debug slot.

CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_chromium_rel_ng;tryserver.blink:linux_blink_rel
R=jgruber@chromium.org

Committed: https://crrev.com/9611a4d24b19a79a78094dbb7e9373b58a71eda4
Cr-Commit-Position: refs/heads/master@{#37107}
==========

[commit-bot: I haz the power, 2016-06-20 14:15:23]

Patchset 1 (id:??) landed as
https://crrev.com/9611a4d24b19a79a78094dbb7e9373b58a71eda4
Cr-Commit-Position: refs/heads/master@{#37107}