Split computeScrollDimensions() out of RenderLayer

Split computeScrollDimensions() out of RenderLayer

This change also moves 2 members of RenderLayer to
RenderLayerScrollableArea and a lot of related code to the
new class. In particular, the after-layout and after-style-change
notification had to be added.

BUG=260899
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=157192

[Ian Vollick, 2013-09-03 14:01:01]

https://codereview.chromium.org/22893055/diff/1/Source/core/rendering/RenderL...
File Source/core/rendering/RenderLayer.cpp (right):

https://codereview.chromium.org/22893055/diff/1/Source/core/rendering/RenderL...
Source/core/rendering/RenderLayer.cpp:2146: {
Since the updating of scroll dimensions now happens via the scrollable area, we
should never call this function directly, right? If that's true, could this be
moved into RenderLayerScrollableArea and hidden away (or at least a warning
comment added)?

https://codereview.chromium.org/22893055/diff/1/Source/core/rendering/RenderL...
Source/core/rendering/RenderLayer.cpp:2929: return
m_scrollableArea->scrollWidth();
Is the plan to eventually update all callers of these passthrough functions to
talk to the RL's scrollable area instead?

[Julien - ping for review, 2013-09-03 22:36:03]

https://codereview.chromium.org/22893055/diff/1/Source/core/rendering/RenderL...
File Source/core/rendering/RenderLayer.cpp (right):

https://codereview.chromium.org/22893055/diff/1/Source/core/rendering/RenderL...
Source/core/rendering/RenderLayer.cpp:2146: {
On 2013/09/03 14:01:01, Ian Vollick wrote:
> Since the updating of scroll dimensions now happens via the scrollable area,
we
> should never call this function directly, right? 

That's totally right.

> If that's true, could this be
> moved into RenderLayerScrollableArea and hidden away (or at least a warning
> comment added)?

Moved per your suggestion.

https://codereview.chromium.org/22893055/diff/1/Source/core/rendering/RenderL...
Source/core/rendering/RenderLayer.cpp:2929: return
m_scrollableArea->scrollWidth();
On 2013/09/03 14:01:01, Ian Vollick wrote:
> Is the plan to eventually update all callers of these passthrough functions to
> talk to the RL's scrollable area instead?

That's exactly the idea. Once we made RenderLayerScrollableArea stand-alone, the
rest of the code should stop assuming it's talking to a RenderLayer.

[Ian Vollick, 2013-09-03 22:48:46]

lgtm

On 2013/09/03 22:36:03, Julien Chaffraix wrote:
>
https://codereview.chromium.org/22893055/diff/1/Source/core/rendering/RenderL...
> File Source/core/rendering/RenderLayer.cpp (right):
> 
>
https://codereview.chromium.org/22893055/diff/1/Source/core/rendering/RenderL...
> Source/core/rendering/RenderLayer.cpp:2146: {
> On 2013/09/03 14:01:01, Ian Vollick wrote:
> > Since the updating of scroll dimensions now happens via the scrollable area,
> we
> > should never call this function directly, right? 
> 
> That's totally right.
> 
> > If that's true, could this be
> > moved into RenderLayerScrollableArea and hidden away (or at least a warning
> > comment added)?
> 
> Moved per your suggestion.
Thanks, that puts me at ease.

> 
>
https://codereview.chromium.org/22893055/diff/1/Source/core/rendering/RenderL...
> Source/core/rendering/RenderLayer.cpp:2929: return
> m_scrollableArea->scrollWidth();
> On 2013/09/03 14:01:01, Ian Vollick wrote:
> > Is the plan to eventually update all callers of these passthrough functions
to
> > talk to the RL's scrollable area instead?
> 
> That's exactly the idea. Once we made RenderLayerScrollableArea stand-alone,
the
> rest of the code should stop assuming it's talking to a RenderLayer.

[commit-bot: I haz the power, 2013-09-04 00:32:21]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/jchaffraix@chromium.org/22893055/6001

[commit-bot: I haz the power, 2013-09-04 04:45:54]

Change committed as 157192