The pixel result of compositing/iframes/resources/repaint-after-losing-scrollbars-iframe.html from DRT shows that the iframes are showing up as opaque white. This reproduces in a WK1 window in Safari.
I think http://trac.webkit.org/changeset/92874 may have broken this. FrameView::useSlowRepaints() returns 'false' for iframes with composited content, but Widget::paint() (in WidgetMac) relies on [[scrollView contentView] copiesOnScroll] to decide when to turn off background drawing.
<rdar://problem/10710494>
WidgetMac really needs to get at FrameView's m_contentIsOpaque bit, but that would be a layering violation.
The relevant test appears to pass as of r115915
compositing/iframes/resources/repaint-after-losing-scrollbars-iframe.html is the iframe source, not the actual test. I probably meant compositing/iframes/repaint-after-losing-scrollbars.html.
(In reply to comment #5) > compositing/iframes/resources/repaint-after-losing-scrollbars-iframe.html is the iframe source, not the actual test. I probably meant compositing/iframes/repaint-after-losing-scrollbars.html. I figured that's what you meant, and that is indeed what I'm referring to.
This still fails. enne, can you look at this?
(In reply to comment #7) > This still fails. enne, can you look at this? Sure, I can take a look.
Created attachment 140636 [details] Patch
(In reply to comment #9) > Created an attachment (id=140636) [details] > Patch I am not happy with this, but am unsure about how else to handle this. I don't think it's correct to assume that !ScrollView::canBlitOnScroll() implies !FrameView::m_contentIsOpaque. It's also very strange to me that drawsBackground is true for something that shouldn't draw a background. That paint function is a pile of assumptions.
smfr: ping
(In reply to comment #11) > smfr: ping smfr: re-ping? You asked me to fix this three weeks ago, so I uploaded a patch. Was this something you wanted landed? Otherwise, maybe this issue should just be WONTFIXed.
Comment on attachment 140636 [details] Patch Sorry for the delay.
Comment on attachment 140636 [details] Patch Clearing flags on attachment: 140636 Committed r118840: <http://trac.webkit.org/changeset/118840>
All reviewed patches have been landed. Closing bug.