Reland of Show Overlay Scrollbar when GestureScrollUpdate

Reland of Show Overlay Scrollbar when GestureScrollUpdate (patchset #2 id:160001 of https://codereview.chromium.org/2748343004/ )

Fix for GPU memory issue:
This issue is caused by more than one DelayedFadeOut task posted. 
So we cancel the previous task before we post a new one.

Original issue's description:
> Revert of Show Overlay Scrollbar when GestureScrollUpdate (patchset #10 id:260001 of https://codereview.chromium.org/2611013002/ )
> 
> Reason for revert:
> memory regression: crbug.com/701810
> 
> Original issue's description:
> > Show Overlay Scrollbar when GestureScrollUpdate
> > 
> > Currently, we only show overlay scrollbars once the page/scroller actually 
> > changes position. In this patch, I also call the 
> > WillUpdateScroll(rename from DidScrollUpdate) when GestureScrollUpdate so we can
> >  show scrollbar when we receive scroll gestures.
> > 
> > BUG=675594
> > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> > 
> > Review-Url: https://codereview.chromium.org/2611013002
> > Cr-Commit-Position: refs/heads/master@{#456474}
> > Committed: https://chromium.googlesource.com/chromium/src/+/b2b25bd2d961354db5081b6090d3782c10513fab
> 
> TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=675594
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> 
> Review-Url: https://codereview.chromium.org/2748343004
> Cr-Commit-Position: refs/heads/master@{#457334}
> Committed: https://chromium.googlesource.com/chromium/src/+/c7a846538699afcb05ba89a8dd8abbf5bbc418ab

TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=675594
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel

Review-Url: https://codereview.chromium.org/2770733002
Cr-Commit-Position: refs/heads/master@{#459077}
Committed: https://chromium.googlesource.com/chromium/src/+/fddbf72985cda9f23f0416c6e6eb1c7714825656

[chaopeng, 2017-03-22 18:49:35]

The CQ bit was checked by chaopeng@chromium.org

[chaopeng, 2017-03-22 18:49:35]

Created Reland of Show Overlay Scrollbar when GestureScrollUpdate

[chaopeng, 2017-03-22 18:49:49]

The CQ bit was unchecked by chaopeng@chromium.org

[chaopeng, 2017-03-22 18:56:11]

Description was changed from

==========
Reland of Show Overlay Scrollbar when GestureScrollUpdate (patchset #2 id:160001
of https://codereview.chromium.org/2748343004/ )

Reason for revert:
For reland.

Original issue's description:
> Revert of Show Overlay Scrollbar when GestureScrollUpdate (patchset #10
id:260001 of https://codereview.chromium.org/2611013002/ )
> 
> Reason for revert:
> memory regression: crbug.com/701810
> 
> Original issue's description:
> > Show Overlay Scrollbar when GestureScrollUpdate
> > 
> > Currently, we only show overlay scrollbars once the page/scroller actually 
> > changes position. In this patch, I also call the 
> > WillUpdateScroll(rename from DidScrollUpdate) when GestureScrollUpdate so we
can
> >  show scrollbar when we receive scroll gestures.
> > 
> > BUG=675594
> > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> > 
> > Review-Url: https://codereview.chromium.org/2611013002
> > Cr-Commit-Position: refs/heads/master@{#456474}
> > Committed:
https://chromium.googlesource.com/chromium/src/+/b2b25bd2d961354db5081b6090d3...
> 
> TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=675594
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> 
> Review-Url: https://codereview.chromium.org/2748343004
> Cr-Commit-Position: refs/heads/master@{#457334}
> Committed:
https://chromium.googlesource.com/chromium/src/+/c7a846538699afcb05ba89a8dd8a...

TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=675594
==========

to

==========
Reland of Show Overlay Scrollbar when GestureScrollUpdate (patchset #2 id:160001
of https://codereview.chromium.org/2748343004/ )

Reason for revert:
For reland.

Original issue's description:
> Revert of Show Overlay Scrollbar when GestureScrollUpdate (patchset #10
id:260001 of https://codereview.chromium.org/2611013002/ )
> 
> Reason for revert:
> memory regression: crbug.com/701810
> 
> Original issue's description:
> > Show Overlay Scrollbar when GestureScrollUpdate
> > 
> > Currently, we only show overlay scrollbars once the page/scroller actually 
> > changes position. In this patch, I also call the 
> > WillUpdateScroll(rename from DidScrollUpdate) when GestureScrollUpdate so we
can
> >  show scrollbar when we receive scroll gestures.
> > 
> > BUG=675594
> > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> > 
> > Review-Url: https://codereview.chromium.org/2611013002
> > Cr-Commit-Position: refs/heads/master@{#456474}
> > Committed:
https://chromium.googlesource.com/chromium/src/+/b2b25bd2d961354db5081b6090d3...
> 
> TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=675594
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> 
> Review-Url: https://codereview.chromium.org/2748343004
> Cr-Commit-Position: refs/heads/master@{#457334}
> Committed:
https://chromium.googlesource.com/chromium/src/+/c7a846538699afcb05ba89a8dd8a...

TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=675594
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

[chaopeng, 2017-03-22 18:56:20]

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

[commit-bot: I haz the power, 2017-03-22 18:57:10]

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

[chaopeng, 2017-03-22 18:58:09]

Description was changed from

==========
Reland of Show Overlay Scrollbar when GestureScrollUpdate (patchset #2 id:160001
of https://codereview.chromium.org/2748343004/ )

Reason for revert:
For reland.

Original issue's description:
> Revert of Show Overlay Scrollbar when GestureScrollUpdate (patchset #10
id:260001 of https://codereview.chromium.org/2611013002/ )
> 
> Reason for revert:
> memory regression: crbug.com/701810
> 
> Original issue's description:
> > Show Overlay Scrollbar when GestureScrollUpdate
> > 
> > Currently, we only show overlay scrollbars once the page/scroller actually 
> > changes position. In this patch, I also call the 
> > WillUpdateScroll(rename from DidScrollUpdate) when GestureScrollUpdate so we
can
> >  show scrollbar when we receive scroll gestures.
> > 
> > BUG=675594
> > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> > 
> > Review-Url: https://codereview.chromium.org/2611013002
> > Cr-Commit-Position: refs/heads/master@{#456474}
> > Committed:
https://chromium.googlesource.com/chromium/src/+/b2b25bd2d961354db5081b6090d3...
> 
> TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=675594
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> 
> Review-Url: https://codereview.chromium.org/2748343004
> Cr-Commit-Position: refs/heads/master@{#457334}
> Committed:
https://chromium.googlesource.com/chromium/src/+/c7a846538699afcb05ba89a8dd8a...

TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=675594
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

to

==========
Reland of Show Overlay Scrollbar when GestureScrollUpdate (patchset #2 id:160001
of https://codereview.chromium.org/2748343004/ )

Add fix for GPU memory issue.

Original issue's description:
> Revert of Show Overlay Scrollbar when GestureScrollUpdate (patchset #10
id:260001 of https://codereview.chromium.org/2611013002/ )
> 
> Reason for revert:
> memory regression: crbug.com/701810
> 
> Original issue's description:
> > Show Overlay Scrollbar when GestureScrollUpdate
> > 
> > Currently, we only show overlay scrollbars once the page/scroller actually 
> > changes position. In this patch, I also call the 
> > WillUpdateScroll(rename from DidScrollUpdate) when GestureScrollUpdate so we
can
> >  show scrollbar when we receive scroll gestures.
> > 
> > BUG=675594
> > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> > 
> > Review-Url: https://codereview.chromium.org/2611013002
> > Cr-Commit-Position: refs/heads/master@{#456474}
> > Committed:
https://chromium.googlesource.com/chromium/src/+/b2b25bd2d961354db5081b6090d3...
> 
> TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=675594
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> 
> Review-Url: https://codereview.chromium.org/2748343004
> Cr-Commit-Position: refs/heads/master@{#457334}
> Committed:
https://chromium.googlesource.com/chromium/src/+/c7a846538699afcb05ba89a8dd8a...

TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=675594
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

[chaopeng, 2017-03-22 18:58:28]

PTAL. Thank you.

[bokan, 2017-03-22 19:18:49]

Please describe in the commit message what the fix for the memory regression is.

Otherwise, lgtm

[chaopeng, 2017-03-22 19:24:30]

Description was changed from

==========
Reland of Show Overlay Scrollbar when GestureScrollUpdate (patchset #2 id:160001
of https://codereview.chromium.org/2748343004/ )

Add fix for GPU memory issue.

Original issue's description:
> Revert of Show Overlay Scrollbar when GestureScrollUpdate (patchset #10
id:260001 of https://codereview.chromium.org/2611013002/ )
> 
> Reason for revert:
> memory regression: crbug.com/701810
> 
> Original issue's description:
> > Show Overlay Scrollbar when GestureScrollUpdate
> > 
> > Currently, we only show overlay scrollbars once the page/scroller actually 
> > changes position. In this patch, I also call the 
> > WillUpdateScroll(rename from DidScrollUpdate) when GestureScrollUpdate so we
can
> >  show scrollbar when we receive scroll gestures.
> > 
> > BUG=675594
> > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> > 
> > Review-Url: https://codereview.chromium.org/2611013002
> > Cr-Commit-Position: refs/heads/master@{#456474}
> > Committed:
https://chromium.googlesource.com/chromium/src/+/b2b25bd2d961354db5081b6090d3...
> 
> TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=675594
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> 
> Review-Url: https://codereview.chromium.org/2748343004
> Cr-Commit-Position: refs/heads/master@{#457334}
> Committed:
https://chromium.googlesource.com/chromium/src/+/c7a846538699afcb05ba89a8dd8a...

TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=675594
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

to

==========
Reland of Show Overlay Scrollbar when GestureScrollUpdate (patchset #2 id:160001
of https://codereview.chromium.org/2748343004/ )

Fix for GPU memory issue:
This issue is caused by more than one DelayedFadeOut task posted. 
So we cancel the previous task before we post a new one.

Original issue's description:
> Revert of Show Overlay Scrollbar when GestureScrollUpdate (patchset #10
id:260001 of https://codereview.chromium.org/2611013002/ )
> 
> Reason for revert:
> memory regression: crbug.com/701810
> 
> Original issue's description:
> > Show Overlay Scrollbar when GestureScrollUpdate
> > 
> > Currently, we only show overlay scrollbars once the page/scroller actually 
> > changes position. In this patch, I also call the 
> > WillUpdateScroll(rename from DidScrollUpdate) when GestureScrollUpdate so we
can
> >  show scrollbar when we receive scroll gestures.
> > 
> > BUG=675594
> > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> > 
> > Review-Url: https://codereview.chromium.org/2611013002
> > Cr-Commit-Position: refs/heads/master@{#456474}
> > Committed:
https://chromium.googlesource.com/chromium/src/+/b2b25bd2d961354db5081b6090d3...
> 
> TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=675594
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> 
> Review-Url: https://codereview.chromium.org/2748343004
> Cr-Commit-Position: refs/heads/master@{#457334}
> Committed:
https://chromium.googlesource.com/chromium/src/+/c7a846538699afcb05ba89a8dd8a...

TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=675594
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

[commit-bot: I haz the power, 2017-03-22 20:04:17]

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

[commit-bot: I haz the power, 2017-03-22 20:04:18]

Dry run: This issue passed the CQ dry run.

[chaopeng, 2017-03-23 14:17:28]

The CQ bit was checked by chaopeng@chromium.org

[commit-bot: I haz the power, 2017-03-23 14:17:51]

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, 2017-03-23 14:24:38]

CQ is committing da patch.

Bot data: {"patchset_id": 180001, "attempt_start_ts": 1490278648450860,
"parent_rev": "1b6af55955d20926d9b75d87fefb4ba15b540284", "commit_rev":
"fddbf72985cda9f23f0416c6e6eb1c7714825656"}

[commit-bot: I haz the power, 2017-03-23 14:25:31]

Description was changed from

==========
Reland of Show Overlay Scrollbar when GestureScrollUpdate (patchset #2 id:160001
of https://codereview.chromium.org/2748343004/ )

Fix for GPU memory issue:
This issue is caused by more than one DelayedFadeOut task posted. 
So we cancel the previous task before we post a new one.

Original issue's description:
> Revert of Show Overlay Scrollbar when GestureScrollUpdate (patchset #10
id:260001 of https://codereview.chromium.org/2611013002/ )
> 
> Reason for revert:
> memory regression: crbug.com/701810
> 
> Original issue's description:
> > Show Overlay Scrollbar when GestureScrollUpdate
> > 
> > Currently, we only show overlay scrollbars once the page/scroller actually 
> > changes position. In this patch, I also call the 
> > WillUpdateScroll(rename from DidScrollUpdate) when GestureScrollUpdate so we
can
> >  show scrollbar when we receive scroll gestures.
> > 
> > BUG=675594
> > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> > 
> > Review-Url: https://codereview.chromium.org/2611013002
> > Cr-Commit-Position: refs/heads/master@{#456474}
> > Committed:
https://chromium.googlesource.com/chromium/src/+/b2b25bd2d961354db5081b6090d3...
> 
> TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=675594
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> 
> Review-Url: https://codereview.chromium.org/2748343004
> Cr-Commit-Position: refs/heads/master@{#457334}
> Committed:
https://chromium.googlesource.com/chromium/src/+/c7a846538699afcb05ba89a8dd8a...

TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=675594
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
==========

to

==========
Reland of Show Overlay Scrollbar when GestureScrollUpdate (patchset #2 id:160001
of https://codereview.chromium.org/2748343004/ )

Fix for GPU memory issue:
This issue is caused by more than one DelayedFadeOut task posted. 
So we cancel the previous task before we post a new one.

Original issue's description:
> Revert of Show Overlay Scrollbar when GestureScrollUpdate (patchset #10
id:260001 of https://codereview.chromium.org/2611013002/ )
> 
> Reason for revert:
> memory regression: crbug.com/701810
> 
> Original issue's description:
> > Show Overlay Scrollbar when GestureScrollUpdate
> > 
> > Currently, we only show overlay scrollbars once the page/scroller actually 
> > changes position. In this patch, I also call the 
> > WillUpdateScroll(rename from DidScrollUpdate) when GestureScrollUpdate so we
can
> >  show scrollbar when we receive scroll gestures.
> > 
> > BUG=675594
> > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> > 
> > Review-Url: https://codereview.chromium.org/2611013002
> > Cr-Commit-Position: refs/heads/master@{#456474}
> > Committed:
https://chromium.googlesource.com/chromium/src/+/b2b25bd2d961354db5081b6090d3...
> 
> TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=675594
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
> 
> Review-Url: https://codereview.chromium.org/2748343004
> Cr-Commit-Position: refs/heads/master@{#457334}
> Committed:
https://chromium.googlesource.com/chromium/src/+/c7a846538699afcb05ba89a8dd8a...

TBR=weiliangc@chromium.org,bokan@chromium.org,pdr@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=675594
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel

Review-Url: https://codereview.chromium.org/2770733002
Cr-Commit-Position: refs/heads/master@{#459077}
Committed:
https://chromium.googlesource.com/chromium/src/+/fddbf72985cda9f23f0416c6e6eb...
==========

[commit-bot: I haz the power, 2017-03-23 14:25:32]

Committed patchset #2 (id:180001) as
https://chromium.googlesource.com/chromium/src/+/fddbf72985cda9f23f0416c6e6eb...