Bug 249869 – Fix missing invalidation when scrollbar is destroyed

• Status: NEW
• Component: Scrolling

[Ahmad Saleem]

Hi Team,

I don't know whether this is needed or it will fix any issue but following is Blink commit:

Blink Commit - https://chromium.googlesource.com/chromium/blink/+/f3a2b99c3c2ee5d435c09ceedcd4a1f213c3baf7

WebKit Source - https://searchfox.org/wubkat/source/Source/WebCore/rendering/RenderLayerScrollableArea.cpp#910 & https://searchfox.org/wubkat/source/Source/WebCore/rendering/RenderLayerScrollableArea.cpp#936

Just wanted to raise, if this is needed or not.

Thanks!

[Radar WebKit Bug Importer]

<rdar://problem/103790698>

[Ahmad Saleem]

Repaint Rects (pre-this change):

Tests invalidation when a scrollbar is destroyed. Passes if there is no scrollbar.
 (repaint rects
  (rect 0 100 100 200)
  (rect 0 100 100 100)
  (rect 0 100 200 200)
  (rect 0 100 200 200)
)


and post this change:

Tests invalidation when a scrollbar is destroyed. Passes if there is no scrollbar.
 (repaint rects
  (rect 0 100 100 200)
  (rect 0 100 100 100)
  (rect 185 100 15 200)
  (rect 0 100 200 200)
  (rect 0 100 200 200)
)

____

Now we have an additional 'rect'.

[Ahmad Saleem]

PR Attempt for future reference - https://github.com/WebKit/WebKit/pull/19001