Continued gradual rollout - dev is not that much riskier than master but will give much more data

Text test should check that a paragraph's longest line is not greater than the width constraint (#67000)

Running a build command with split debug info and analyze size causes a crash in the snapshot analysis library. Disable the combination of these two flags.

Fixes #66962

* Set DDS port to requested observatory port for test

* Add test for DDS and observatory ports

* Use FakePlatform instead of mock, fix spacing

* Use FakeProcessManager instead of mock

* Fix analyze issue

* Make completer private and add fn for future

In cases where the VSCode plugins are not located, display links to where they can be downloaded but do not surface an error.

d18c3ea75 Roll Skia from 0b0fb4d50b75 to 9ecb3abfdfe8 (12 revisions) (flutter/engine#21500) (#66942)

Re-arrange the implementation of the devtools launcher so that google3 is not required to depend on any devtools packages. Also renames the build_runner folders to isolated to better clarify their intention.

In cases where the Intellij/AS plugins are not located, display links to where they can be downloaded but do not surface an error. This should generally reduce confusion about whether the plugins are required for every installed IDE. For example, frequently users may only install AS so that they can install the Android SDK - or they may have multiple copies of Intellij installed.

For example: #66762

This reverts commit 73b63989.

* migrate some material files to nullsafty

* address review comments

Crash reporting shows at least one occurrence of this due to a windows file lock. That could happen if there is another running chrome instance, or perhaps a virus scanner is running. Print out the error and do not crash.

5a7336ef2 Roll Dart SDK from 4c0245356649 to 4ea46a8b10a1 (1 revision) (flutter/engine#21482) (#66913)

Improve GlobalKey docs by mentioning a pitfall that some users had where the instantiated it in the build method.

it is possible for users that download the prebuilt SDKs to run the tool without unzip installed. Rather than crashing with an unclear argument error, exit the tool with a message on how to install that mirrors the message in the update_dart_sdk.sh script.

Also applied to zip for completeness

This is a continuation of https://github.com/flutter/flutter/pull/61366
after cl/333620714

See also https://flutter.dev/go/clip-behavior

The previously broken test should be fixed by
https://github.com/flutter/gallery/pull/331