[webkit-reviews] review granted: [Bug 78008] Investigate rubberbanding/transform-overhang-[e|se|s].html failures : [Attachment 127583] Patch

[bugzilla-daemon at webkit.org]

James Robinson <jamesr at chromium.org> has granted asvitkine at chromium.org's
request for review:
Bug 78008: Investigate rubberbanding/transform-overhang-[e|se|s].html failures
https://bugs.webkit.org/show_bug.cgi?id=78008

Attachment 127583: Patch
https://bugs.webkit.org/attachment.cgi?id=127583&action=review

------- Additional Comments from James Robinson <jamesr at chromium.org>
View in context: https://bugs.webkit.org/attachment.cgi?id=127583&action=review


Seems OK, but this weird mix of ScrollView/FrameView/RenderLayerCompositor for
overhang areas is really annoying to try to understand and debug.

On mac !CHROMIUM, the ScrollbarTheme sets up the overhang area layer to just be
a tiled pattern and the shadow layer to be some sort of magic path-based layer.
we don't support either of those in our compositor today, but I think we could
with not too much effort. I think we'd be much better off using an approach
like that rather than manually repainting + reuploading this overhang layer all
the time.  I suspect you won't want to work on improving this, but would you
mind filing some bugs to improve this?	I'm not super confident in our ability
to maintain the current code.

> Source/WebCore/platform/ScrollView.h:285
> +    void updateOverhangAreas();

this should be private

calculate...() probably should be private as well