There are some problems to use fixedLayout in the WebKit2, so I made patch for that. When we change the fixedLayout UIProcess's variables are set firstly, and then requests to apply changed fixedLayout are sended to the WebProcess. In that case, UIProcess keeps changed values even though WebProcess fails to set fixedLayout. So I changed codes to set UIProcess's fixedLayout variables when didChange message is received from WebProcess instead of setting directly. The fixedLayout variables are reset whenever creating new FrameView. It breaks consistency of UIProcess's fixedLayout variables and WebProcess's ones. So I modified codes to maintain old FrameView's fixedLayout variables.
Created attachment 104449 [details] Patch for FixedLayout
Created attachment 107842 [details] Patch for FixedLayout Rebase patch.
One of the WK2 reviewers should be able to tell you if this is right.
WebPage.cpp's setUseFixedLayout() and setFixedLayoutSize() were changed to check mainFrameView by https://bugs.webkit.org/show_bug.cgi?id=73212. So, WebPage's fixed layout functions will not fail and I don't have to return the fixedLayout variables back to the UIProcess. The codes to maintain old fixedLayout variables were merged by https://bugs.webkit.org/show_bug.cgi?id=72511. So, this bug is not needed anymore and I want to change state to RESOLVED.
Comment on attachment 107842 [details] Patch for FixedLayout Cleared review? from attachment 107842 [details] so that this bug does not appear in http://webkit.org/pending-review. If you would like this patch reviewed, please attach it to a new bug (or re-open this bug before marking it for review again).