* Roll the engine.

This engine includes a VM that defaults to sync-async.

flutter/engine@c8eeee4 Roll the Dart VM.

Seems like VS Code may have started using lowercase extension folders recently (our identifier is `Dart-Code.flutter` but now the folder is named `dart-code.flutter`), so this makes the check not sensitive to casing.

Also reuse extension identifier for download link

... and make sure they fail if they can't report the size.

This reverts commit 77508722.

We have many hidden children because of iOS accessibility (see also #18410).

For example, in the tile screen of complex_layout app, there could be up to 20 children being painted without this PR. With this PR, only 12 get painted.

This should improve the performance of FL-53 by 40%.

Add flutter tool support for creating app-specific VM snapshots.

Fixes #10826.

Also in this PR: If you focus a text field, scroll it out of view and then start typing it will scroll back into view.

This reverts commit e593dc70.

"flutter update-packages --force-upgrade"

(second attempt)

When setState() calls occur asynchronously, it's possible that the
Futures on which they're waiting don't complete until the widget is
offscreen. To avoid this, we check the widget is mounted before calling
setState().

* Fix readme link to plugin edit instructions

* Fix flutter tools link

fuchsia_tester.dart still assumes Dart 1. Previously, it ran tests directly
from source, flutter_platform.dart automatically runs a kernel compile when
operating in Dart 2 mode, but this assumes a functional Dart SDK is available
in the artifacts directly, and fuchsia_tester.dart mocks out the artifacts
directory with an empty temp dir.

Remaining work is:
1. Get the frontend server building as a dependency on Fuchsia.
2. Patch fuchsia_tester.dart to use a valid Dart SDK and frontend server.

This also reverts migration to Dart 2 typedef syntax.

This reverts commit 6c56bb24. (#18362)
This reverts commit 3daebd05. (#18316)

Fix ListView dartdoc where a paragraph doesn't flow with the section heading and the other paragraphs in the section (#18430)

Similar to the flutter driver, now the fuchsia_remote_debug_protocol can
connect via an environment variable. This can also be used to point to
the SSH config location.

This makes it so that tests written using the FRDB do not have to write
extra information about where their device is on the network.

* Fix anchors for GitHub

For some reason GitHub lowercases the anchor names so although these links all work in the local VS Code preview, the ones with capitals didn't work in the GitHub UI!

* Fix some typos

flutter/engine@c3976b3 Revert "Added IsolateNameServer functionality (#5410)"
flutter/engine@61a2d12 Added IsolateNameServer functionality
flutter/engine@412f8b8 Roll src/third_party/skia 8ea971bfefb6..bb9ee9b4aa7d (10 commits)
flutter/engine@3b1f381 Expose approximateBytesUsed for Picture
flutter/engine@a4c8e1f Roll src/third_party/skia 2a2f67592602..8ea971bfefb6 (5 commits)

* Roll the engine

flutter/engine@6b1b887 Roll the Dart VM.

flutter/engine@a328531 Roll src/third_party/skia 8e4d09ae7af1..2a2f67592602 (6 commits)
    flutter/engine@10850ea Roll src/third_party/skia 0e2608e84fe5..8e4d09ae7af1 (1 commits)
    flutter/engine@59a784d Roll src/third_party/skia 8c6b49718210..0e2608e84fe5 (1 commits)
    flutter/engine@c0ba226 Roll src/third_party/skia 5c12122ad91d..8c6b49718210 (1 commits)
    flutter/engine@be02d0c Revert "Eliminate support for Dart 1 (#5504)"
    flutter/engine@0ea93c3  Eliminate support for Dart 1
    flutter/engine@036443d Roll src/third_party/skia 36f0c41eafe9..5c12122ad91d (5 commits)
    flutter/engine@4c91156 Roll src/third_party/skia 46fbf8c97a13..36f0c41eafe9 (5 commits)
    flutter/engine@782e500 Roll src/third_party/skia 4c4650150d5f..46fbf8c97a13 (1 commits)
    flutter/engine@16ea70b Roll src/third_party/skia 27dddae3130c..4c4650150d5f (16 commits)