Adjust visual overflow rect for rounded/shifted ascent/descent

Adjust visual overflow rect for rounded/shifted ascent/descent

For now we round and/or shift ascent and descent to integers in some cases,
and we may layout using ascent/descent smaller than the original, causing that
painted text at the laid-out position may overflow the visual overflow
calculated based on layout geometries.

Now record the loss in FontMetrics and adjust visual overflow rect to cover
the overflows.

BUG=706298
TBR=wangxianzhu@chromium.org
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2803483002
Cr-Original-Commit-Position: refs/heads/master@{#464689}
Review-Url: https://codereview.chromium.org/2819953002
Cr-Commit-Position: refs/branch-heads/3029@{#721}
Cr-Branched-From: 939b32ee5ba05c396eef3fd992822fcca9a2e262-refs/heads/master@{#454471}
Committed: https://chromium.googlesource.com/chromium/src/+/74f0a8230b1018a1071cd07beff0e3d6470a9ae4

[Xianzhu, 2017-04-14 22:15:47]

Description was changed from

==========
Adjust visual overflow rect for rounded/shifted ascent/descent

For now we round and/or shift ascent and descent to integers in some cases,
and we may layout using ascent/descent smaller than the original, causing that
painted text at the laid-out position may overflow the visual overflow
calculated based on layout geometries.

Now record the loss in FontMetrics and adjust visual overflow rect to cover
the overflows.

BUG=706298

Review-Url: https://codereview.chromium.org/2803483002
Cr-Commit-Position: refs/heads/master@{#464689}
==========

to

==========
Adjust visual overflow rect for rounded/shifted ascent/descent

For now we round and/or shift ascent and descent to integers in some cases,
and we may layout using ascent/descent smaller than the original, causing that
painted text at the laid-out position may overflow the visual overflow
calculated based on layout geometries.

Now record the loss in FontMetrics and adjust visual overflow rect to cover
the overflows.

BUG=706298
TBR=wangxianzhu@chromium.org
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2803483002
Cr-Commit-Position: refs/heads/master@{#464689}
==========

[Xianzhu, 2017-04-14 22:15:50]

The CQ bit was checked by wangxianzhu@chromium.org

[commit-bot: I haz the power, 2017-04-14 22:16:12]

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, 2017-04-14 22:21:01]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1492208150236890,
"parent_rev": "9302f10628d14eba1e0e8cf953813330b35f50c8", "commit_rev":
"74f0a8230b1018a1071cd07beff0e3d6470a9ae4"}

[commit-bot: I haz the power, 2017-04-14 22:21:58]

Description was changed from

==========
Adjust visual overflow rect for rounded/shifted ascent/descent

For now we round and/or shift ascent and descent to integers in some cases,
and we may layout using ascent/descent smaller than the original, causing that
painted text at the laid-out position may overflow the visual overflow
calculated based on layout geometries.

Now record the loss in FontMetrics and adjust visual overflow rect to cover
the overflows.

BUG=706298
TBR=wangxianzhu@chromium.org
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2803483002
Cr-Commit-Position: refs/heads/master@{#464689}
==========

to

==========
Adjust visual overflow rect for rounded/shifted ascent/descent

For now we round and/or shift ascent and descent to integers in some cases,
and we may layout using ascent/descent smaller than the original, causing that
painted text at the laid-out position may overflow the visual overflow
calculated based on layout geometries.

Now record the loss in FontMetrics and adjust visual overflow rect to cover
the overflows.

BUG=706298
TBR=wangxianzhu@chromium.org
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2803483002
Cr-Original-Commit-Position: refs/heads/master@{#464689}
Review-Url: https://codereview.chromium.org/2819953002
Cr-Commit-Position: refs/branch-heads/3029@{#721}
Cr-Branched-From:
939b32ee5ba05c396eef3fd992822fcca9a2e262-refs/heads/master@{#454471}
Committed:
https://chromium.googlesource.com/chromium/src/+/74f0a8230b1018a1071cd07beff0...
==========

[commit-bot: I haz the power, 2017-04-14 22:21:59]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/chromium/src/+/74f0a8230b1018a1071cd07beff0...