[webkit-changes] [WebKit/WebKit] b9473e: [Site Isolation] Exposed content rect of subframe ...

[Sihui]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: b9473ec1d60adf0b5325f08907893928d2df946f
      https://github.com/WebKit/WebKit/commit/b9473ec1d60adf0b5325f08907893928d2df946f
  Author: Sihui Liu <sihui_liu at apple.com>
  Date:   2024-02-08 (Thu, 08 Feb 2024)

  Changed paths:
    M LayoutTests/platform/ios/TestExpectations
    M Source/WebKit/WebProcess/WebPage/WebPage.cpp

  Log Message:
  -----------
  [Site Isolation] Exposed content rect of subframe view is wrong
https://bugs.webkit.org/show_bug.cgi?id=268647
rdar://122199122

Reviewed by Simon Fraser and Alex Christensen.

On iOS, exposedContentRect of FrameView is used to decide visible area that needs compositing update (see
RenderLayerCompositor::visibleRectForLayerFlushing and RenderLayerCompositor::flushPendingLayerChanges). Currently
exposedContentRect is set via DrawingArea (and each DrawingArea has one content rect), and it is only set on the main
frame view (as child frames can inheirt the value from their parent, see ScrollView::exposedContentRect()). That means
frames in the subframe process do not have the correct content rect and thus do not render. To fix that, now we set the
exposedContentRect of those frames to be the frame rect. This is a temporary fix that enables us to run tests; we are
going to make a complete fix that ensures UI process sends geometry updates to web process in rdar://122429810.

* LayoutTests/platform/ios/TestExpectations:
* Source/WebKit/WebProcess/WebPage/WebPage.cpp:
(WebKit::WebPage::updateFrameSize):

Canonical link: https://commits.webkit.org/274302@main