Relative offsets should be applied after fragmentation. Since we perform
layout for OOFs once they reach the fragmentation context root (if
applicable), we fail to apply any relative offsets at the correct time
in the case of inline containing blocks. See CL:2851595 for how this
was handled for the non-inline case.

The changes required to accomplish this for inline containing blocks
include:

1. We currently store an accumulated relative offset in
NGContainingBlock inside the OOF node, which is any relative offset from
the containing block to the fragmentation context root. We also need to
store an accumulated relative offset from the inline container to the
containing block in order to properly apply all relative offsets at the
time of fragmentation.

A new struct, NGInlineContainer, was added to the OOF node to hold the
inline container object and the accumulated relative offset to the
containing block.

2. A relative offset was also added to the InlineContainingBlockGeometry
struct so that we have access to the relative offset from #1 when
creating the ContainingBlockInfo for the inline container.

3. The way that relative offsets are applied to inlines, it didn't seem
straightforward to separate the relative offset from the normal
offset, like we had in CL:2851595. Instead, store the relative offset
for the inline and subtract it out from the OOF static position once
it reaches the containing block, and subtract it from the containing
block rect offset when determining the ContainingBlockInfo for the
inline container.

4. Store the total relative offset (from the inline container to the
fragmentation context root) in ContainingBlockInfo. This relative
offset will then be applied after fragmentation is complete for the OOF
as a result of CL:2851595.

Bug: 1079031
Change-Id: I7198fec4c01e05ca54c51b2f215569b75b0b869e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2995308
Commit-Queue: Alison Maher <almaher@microsoft.com>
Reviewed-by: Morten Stenshorne <mstensho@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#902060}

This patch adds a new produceCropId() API to mediaDevices.

This API is called with a DIV or IFRAME element, and adds a new
base::UnguessableToken value to that element's rare data structure.

This token value will be used in followup patches in order to keep track
of an element's location in the page and viewport.

Based on the following design document:
https://docs.google.com/document/d/1dULARMnMZggfWqa_Ti_GrINRNYXGIli3XK9brzAKEV8/

Bug: 1247761
Change-Id: I01cd67e2d4e3dfa7a86289f876e48c8b55095d0a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3173396
Commit-Queue: Jordan Bayles <jophba@chromium.org>
Reviewed-by: Elad Alon <eladalon@chromium.org>
Reviewed-by: mark a. foltz <mfoltz@chromium.org>
Reviewed-by: Joey Arhar <jarhar@chromium.org>
Cr-Commit-Position: refs/heads/main@{#925544}

…eVisibilityKeeper::PrepareToSplitBlockElement()` before splitting a text node

It does the following things when caret is collapsed in a text node in a `<p>`
or `<div>` element.

1. Split the text node containing caret to insert `<br>` element
2. Insert `<br>` element after it
3. Split ancestor elements which inclusive descendants of the `<p>` or `<div>`
4. Delete the `<br>` element if unnecessary from the left paragraph

#3 and #4 are performed by `HTMLEditor::SplitParagraph()` and it calls
`WhiteSpaceVisibilityKeeper::PrepareToSplitBlockElement()` correctly before
splitting the block.  However, in the case (caret is at middle of a text node),
the text has already been split to 2 nodes because of #1.  Therefore, it fails
to handle to keep the white-space visibility.

So that I believe that the root cause of this bug is, the method does much
complicated things which are required, and doing the redundant things will
eat memory space due to undo transactions.  However, for now, I'd like to fix
this with a simple patch which just call the preparation method before splitting
the text node because I'd like to uplift this if it'd be approved (Note that
this is not a recent regression, the root cause was created by bug 92686 which
was fixed in 17 years ago:
<https://searchfox.org/mozilla-central/commit/2e66280faef73e9be218e00758d4eb738395ac83>,
but must be annoying bug for users who see this frequently).

The new WPTs are pass in Chrome.

Differential Revision: https://phabricator.services.mozilla.com/D130950

bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1740416
gecko-commit: 73567f6c2bcfa078836a36760498bb11747561dd
gecko-reviewers: m_kato, smaug

By adding new exhaustive tests under ordering/, it was revealed that the ordering between navigatesuccess/navigateerror and the committed/finished promises was not always consistent:

1. Simply adding a currentchange event handler would cause microtasks to run during commit, which changed some ordering.

2. Calling transitionWhile() would take us from the zero-promise case to the 1+-promise case in ScriptPromise::All(). As the new comment explains, both the spec and implementation have an observably-different fast path for the 0-promise case which caused changes in ordering.

In the course of fixing this, I found out that the did_finish_before_commit_ code in app_history_api_navigation.{h,cc} was actually not a mitigation for the case it stated, where promises passed to transitionWhile() would settle faster than the browser-process roundtrip for same-document traversals. That is in fact impossible, since we only fire the navigate event after the browser-process roundtrip has completed. Instead, they were a mitigation for (1).

This commit then ensures consistent ordering, tested with new rather-exhaustive tests, in the following manner:

* We move the firing of currentchange to before resolving the committed promise. This eliminates (1) and allows us to delete the did_finish_before_commit_ tracking.

* We always ensure we pass 1+ promises to ScriptPromise::All(). This eliminates (2).

A consequence of this is that we are now more likely to get rejected finished promises, in cases like

    await appHistory.navigate("#1").committed;
    await appHistory.navigate("#2").committed;

Before, the finished promise for the #1 navigation would go through the fast path per (2), and fulfill before the navigation to #2 canceled it. Now that does not happen, so code like the above will give an unhandled promise rejection for #1's finished promise.

To avoid this, we unconditionally mark finished promises as handled. This follows some web platform precedent, e.g. stream closed promises, where the promise is one of several information channels (in this case the developer might also find out via the AbortSignal or the navigateerror event). We do *not* do this for the committed promise though, as if a commit fails, that's probably something more deeply wrong, and cannot be ignored.

All of these changes will require spec updates.

For the tests, we introduce a new ordering/ directory which contains cross-cutting ordering tests, and we consolidate a few tests into the newly-introduced variant-driven exhaustive ones. A couple of other tests were affected by these changes too or fixed as a drive-by.

Change-Id: I8a50ca28d009e0a8a2c94331cd17f29b0a8dc463
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3405377
Reviewed-by: Nate Chapin <japhet@chromium.org>
Commit-Queue: Domenic Denicola <domenic@chromium.org>
Cr-Commit-Position: refs/heads/main@{#963772}