Bug 13037 – REGRESSION: Copy-on-scroll not reset properly after back/forward navigation

• Status: RESOLVED
• Resolution: FIXED
• Component: Page Loading

Summary:
After navigating back and forth through the b/f cache, the web view is set to "copy on scroll" despite having content that should prohibit such behavior (e.g. fixed background).

To reproduce:
1) Go to <http://www.w3.org/TR/CSS21/>.
2) Click on the "next" link.
3) Go back.
4) Go forward.
5) Scroll up and down.

Expected result:
The "W3 Working Draft" banner on the left to remain fixed and not scroll out of view.

Actual result:
The "W3 Working Draft" banner scrolls out of view when scrolling down, and artifacts appear when scrolling up.

Regression:
Yes, this doesn't happen in shipping Safari.

Notes:
While this is a rendering bug, it's ultimately caused by the page loading machinery not (re)setting up the view properly, so I'm filing under Page Loading.

[Mark Rowe (bdash)]

<rdar://problem/5061030>

Regressed in <http://trac.webkit.org/projects/webkit/changeset/13440>.

Actually the regression in r13440 was fixed in r13649 (fix for bug 8079). It came back later.

Most recently regressed in <http://trac.webkit.org/projects/webkit/changeset/15722> (fix for bug 10179).

Created attachment 14415 [details]
Keep the slow repaint object count intact and non-negative

[Dave Hyatt]

Comment on attachment 14415 [details]
Keep the slow repaint object count intact and non-negative

r=me

[Mark Rowe (bdash)]

Landed in r21329.