commit 8b0fc98526c83ad801481ac289323e70ef2d6e10
author Hiroki Nakagawa <nhiroki@chromium.org> Tue Nov 05 06:00:54 2024
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Tue Nov 05 06:00:54 2024
tree c59ee4000d111a23fe2cb557571bca0d5e801635
parent 8fc885dc9eb23bdd9dc1bab546c5c9f39491c226

Prerender: Don't call DidStopLoading on activation when it's not reached

> Background of this change

Load events on a prerendered page are deferred until prerender
activation by design. WebContentsObserver::DidStopLoading is one of the
events.

When a prerendered page is loaded, FrameTree::Delegate::DidStopLoading
is called. In non-prerendering cases, the delegate is WebContentsImpl
that notifies WebContentsObserver::DidStopLoading. On the other hand,
in prerendering cases, the delegate is PrerenderHost that ignores the
event, and instead RenderFrameHostImpl::DidCommitPageActivation
*unconditionally* calls DidStopLoading when a prerendered page gets
activated. Deferral of DidStopLoading is implemented in this way.

This should work well when the prerendered page has already reached
DidStopLoading before activation, but does not work when the page
hasn't reached it yet. DidCommitPageActivation notifies the observers of
DidStopLoading, while the page is still being loaded. This results in
confusing the loading state management.

> Solution

To fix this, this CL invokes DidStopLoading on activation only when a
prerendered page has already reached the milestone. The condition is
tracked with DocumentAssociatedData.

Change-Id: I40adff7074eaa51fb74692a112ad10809bed5ff0
Bug: 40256454
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5980111
Reviewed-by: Rakina Zata Amni <rakina@chromium.org>
Commit-Queue: Hiroki Nakagawa <nhiroki@chromium.org>
Reviewed-by: Lingqi Chi <lingqi@chromium.org>
Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1378130}