Need to be inside the flow thread before converting a visual point.

Need to be inside the flow thread before converting a visual point.

Before we can convert from a visual point to a flow thread point, we need the
input point to be exactly relative to the flow thread, or we might end up
mapping it to the wrong column.

In other words, we need to add the flow thread object's location before
converting into the flow thread coordinate space. While the flow thread indeed
is at 0,0 (or at least close enough to 0,0) relatively to the multicol
container in very many cases, this isn't true when the multicol container is in
rtl writing-mode, or when it's scrollable, or even when the multicol container
has borders and/or padding.

BUG=663062
Committed: https://crrev.com/797ecc9d67798296b6c8fd2ced17f4716ccbb111
Cr-Commit-Position: refs/heads/master@{#439855}

[mstensho (USE GERRIT), 2016-12-20 13:19:47]

The CQ bit was checked by mstensho@opera.com to run a CQ dry run

[commit-bot: I haz the power, 2016-12-20 13:20:03]

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, 2016-12-20 14:59:35]

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

[commit-bot: I haz the power, 2016-12-20 14:59:35]

Dry run: This issue passed the CQ dry run.

[mstensho (USE GERRIT), 2016-12-20 15:24:54]

mstensho@opera.com changed reviewers:
+ eae@chromium.org, szager@chromium.org

[szager1, 2016-12-20 17:55:50]

lgtm, good catch

[mstensho (USE GERRIT), 2016-12-20 18:42:38]

The CQ bit was checked by mstensho@opera.com

[commit-bot: I haz the power, 2016-12-20 18:43:04]

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, 2016-12-20 18:50:19]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1482259358066250, "parent_rev":
"e3a425fdd26a8e5d131e89c5698ea808d8dbcd1b", "commit_rev":
"c87af8596f8bd773e89b2ac14451db9e8898d717"}

[commit-bot: I haz the power, 2016-12-20 18:50:48]

Description was changed from

==========
Need to be inside the flow thread before converting a visual point.

Before we can convert from a visual point to a flow thread point, we need the
input point to be exactly relative to the flow thread, or we might end up
mapping it to the wrong column.

In other words, we need to add the flow thread object's location before
converting into the flow thread coordinate space. While the flow thread indeed
is at 0,0 (or at least close enough to 0,0) relatively to the multicol
container in very many cases, this isn't true when the multicol container is in
rtl writing-mode, or when it's scrollable, or even when the multicol container
has borders and/or padding.

BUG=663062
==========

to

==========
Need to be inside the flow thread before converting a visual point.

Before we can convert from a visual point to a flow thread point, we need the
input point to be exactly relative to the flow thread, or we might end up
mapping it to the wrong column.

In other words, we need to add the flow thread object's location before
converting into the flow thread coordinate space. While the flow thread indeed
is at 0,0 (or at least close enough to 0,0) relatively to the multicol
container in very many cases, this isn't true when the multicol container is in
rtl writing-mode, or when it's scrollable, or even when the multicol container
has borders and/or padding.

BUG=663062

Review-Url: https://codereview.chromium.org/2593633002
==========

[commit-bot: I haz the power, 2016-12-20 18:50:49]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-12-20 18:54:06]

Description was changed from

==========
Need to be inside the flow thread before converting a visual point.

Before we can convert from a visual point to a flow thread point, we need the
input point to be exactly relative to the flow thread, or we might end up
mapping it to the wrong column.

In other words, we need to add the flow thread object's location before
converting into the flow thread coordinate space. While the flow thread indeed
is at 0,0 (or at least close enough to 0,0) relatively to the multicol
container in very many cases, this isn't true when the multicol container is in
rtl writing-mode, or when it's scrollable, or even when the multicol container
has borders and/or padding.

BUG=663062

Review-Url: https://codereview.chromium.org/2593633002
==========

to

==========
Need to be inside the flow thread before converting a visual point.

Before we can convert from a visual point to a flow thread point, we need the
input point to be exactly relative to the flow thread, or we might end up
mapping it to the wrong column.

In other words, we need to add the flow thread object's location before
converting into the flow thread coordinate space. While the flow thread indeed
is at 0,0 (or at least close enough to 0,0) relatively to the multicol
container in very many cases, this isn't true when the multicol container is in
rtl writing-mode, or when it's scrollable, or even when the multicol container
has borders and/or padding.

BUG=663062

Committed: https://crrev.com/797ecc9d67798296b6c8fd2ced17f4716ccbb111
Cr-Commit-Position: refs/heads/master@{#439855}
==========

[commit-bot: I haz the power, 2016-12-20 18:54:07]

Patchset 1 (id:??) landed as
https://crrev.com/797ecc9d67798296b6c8fd2ced17f4716ccbb111
Cr-Commit-Position: refs/heads/master@{#439855}