Adjust maximum scroll bounds on FrameView to account for top controls. (Chromium-side)

Adjust maximum scroll bounds on FrameView to account for top controls. (Chromium-side)

The compositor adjusts the viewport bounds based on how far the top
controls are shown; however, the resize of the viewport on the Blink
side doesn't happen until a Resize event is received, which is heavily
throttled. This means that when a commit happens before the Resize,
the scroll offsets given to Blink may be outside the maximum bounds
and will be incorrectly clamped.

This CL adjusts FrameView's maximumScrollPosition to account for the
drift in where Blink and the Compositor think the top controls are.

Blink-side: https://codereview.chromium.org/560623002/

BUG=412581
Committed: https://crrev.com/0c93cd876ca4a6763398cb68fbac7eef582d5db8
Cr-Commit-Position: refs/heads/master@{#297478}

[bokan, 2014-09-24 14:35:02]

bokan@chromium.org changed reviewers:
+ jamesr@chromium.org

[bokan, 2014-09-24 14:35:03]

+jamesr@ for Chromium-side of already landed
https://codereview.chromium.org/560623002/

[jamesr, 2014-09-24 18:41:12]

lgtm, although if we're setting this here can you remind me why this parameter
is not simply part of the resize call?

[bokan, 2014-09-24 19:11:59]

On 2014/09/24 18:41:12, jamesr wrote:
> lgtm, although if we're setting this here can you remind me why this parameter
> is not simply part of the resize call?

You mean the WebWidget::resize? I suppose it could be but since top controls are
often not applicable it might needlessly confuse callers.

[bokan, 2014-09-24 19:14:52]

On 2014/09/24 19:11:59, bokan wrote:
> On 2014/09/24 18:41:12, jamesr wrote:
> > lgtm, although if we're setting this here can you remind me why this
parameter
> > is not simply part of the resize call?
> 
> You mean the WebWidget::resize? I suppose it could be but since top controls
are
> often not applicable it might needlessly confuse callers.

Though I suppose a top controls layout height change implies a size
change...would you prefer changing setTopControlsLayoutHeight to a resize
overload with a tclh param?

[jamesr, 2014-09-24 20:25:12]

If we always specify the same thing it doesn't sound too confusing.  Is the
timing always exactly the same as the resize call?  I'm slightly worried about
the two getting out of sync.

[bokan, 2014-09-24 20:37:47]

On 2014/09/24 20:25:12, jamesr wrote:
> If we always specify the same thing it doesn't sound too confusing.

I meant the other 'non-RenderWidget' users of WebWidget, where top controls
don't exist.

> Is the timing always exactly the same as the resize call?  I'm slightly
worried
> about the two getting out of sync.

Yes, it is. In that case, is an overload of resize that takes the two params ok?

[bokan, 2014-09-26 18:04:15]

On 2014/09/24 20:37:47, bokan wrote:
> On 2014/09/24 20:25:12, jamesr wrote:
> > If we always specify the same thing it doesn't sound too confusing.
> 
> I meant the other 'non-RenderWidget' users of WebWidget, where top controls
> don't exist.
> 
> > Is the timing always exactly the same as the resize call?  I'm slightly
> worried
> > about the two getting out of sync.
> 
> Yes, it is. In that case, is an overload of resize that takes the two params
ok?

ping.

[bokan, 2014-09-29 18:08:11]

Hey James, would you prefer the call to be WebWidget::resize(size,
topControlsLayoutSize)? Or something else?

[bokan, 2014-09-30 18:00:59]

On 2014/09/29 18:08:11, bokan wrote:
> Hey James, would you prefer the call to be WebWidget::resize(size,
> topControlsLayoutSize)? Or something else?

I'm going to land this as-is since it's blocking some of my other work. I'll
happily make any changes after the fact.

[bokan, 2014-09-30 18:01:05]

The CQ bit was checked by bokan@chromium.org

[commit-bot: I haz the power, 2014-09-30 18:02:54]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/563513002/20001

[commit-bot: I haz the power, 2014-09-30 19:20:50]

Committed patchset #2 (id:20001) as 03858aa169abeeaffe138f155042cee3d4fcd683

[commit-bot: I haz the power, 2014-09-30 19:21:26]

Patchset 2 (id:??) landed as
https://crrev.com/0c93cd876ca4a6763398cb68fbac7eef582d5db8
Cr-Commit-Position: refs/heads/master@{#297478}