* Revert "docs for image disposal (#67066)"

This reverts commit bcb2ac5a.

* Revert "Dispose of images after using them (#66688)"

This reverts commit a7954691.

Fixes https://github.com/flutter/flutter/issues/66569

SkParagraph may calculate slightly different metrics for text layouts

* Dispose of images after using them
Adds ImageInfo.clone, ImageInfo.dispose, and ImageInfo.isCloneOf.
Makes all stateful holders of ui.Image objects properly clone and dispose of them.
Behavior change for ImageStreamCompleter: Removing the last listener after registering at least one listener results in the object being disposed, and new listeners cannot be added, unless a keepAlive handle is created.
Makes all non-stateful holders of ui.Image (i.e. paintImage and RawImage) assert that whoever gave the image to them has not disposed it on them.

* migrate some material files to nullsafety

* fix test_private

* address review comments

* fix private test on windows

* use uri in include entry of analysis_options

572c34356 add checker board for clip_path,clip_rect,clip_rrect,physical_shap_layer (flutter/engine#20997) (#67010)

package:http can throw a ClientException, which the crash reporter must catch or the tool will crash in the crash reporter. 3/4 crash on dev.

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.