The current API was broken in that you registered multiple
callbacks at once, but when you removed listeners, only the
primary listener was used to determine what was removed.
This led to unintuitive cases where the caller could get
unexpected behavior.

This updates the API to add and remove listeners using
a newly introduced [ImageStreamListener] object, a value
object that has references to the individual callbacks
that may fire.

flutter/flutter#24722
flutter/flutter#32374
flutter/flutter#32935

This function is called frequently with non-repeating images during many
animations

* add trailing commas on list/map/parameters

* add trailing commas on Invocation with nb of arg>1

* add commas for widget containing widgets

* add trailing commas if instantiation contains trailing comma

* revert bad change

* Added a filterQuality parameter to images.

* Removed this break by accident.

* Modified the test case to check the filterQuality

* Update packages/flutter/lib/src/rendering/image.dart
Co-Authored-By: namanix <namanix@gmail.com>

* Update packages/flutter/lib/src/rendering/image.dart
Co-Authored-By: namanix <namanix@gmail.com>

* Update packages/flutter/lib/src/rendering/image.dart
Co-Authored-By: namanix <namanix@gmail.com>

* Update packages/flutter/lib/src/widgets/image.dart
Co-Authored-By: namanix <namanix@gmail.com>

* Update packages/flutter/lib/src/widgets/image.dart
Co-Authored-By: namanix <namanix@gmail.com>

* Update packages/flutter/lib/src/rendering/image.dart
Co-Authored-By: namanix <namanix@gmail.com>

* Update packages/flutter/lib/src/rendering/image.dart
Co-Authored-By: namanix <namanix@gmail.com>

* Added documentation for the new parameter and corrected some space issue's

* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

* Scale high-pixel-ratio images with BoxFit.none/BoxFit.scaleDown correctly

* add test cases for image scale

* make analyzer happy

* Make sure that test images always have a scale to make all tests pass

* add a new author

* use new keyword in tests

Fixes https://github.com/flutter/flutter/issues/12553

The root cause of https://github.com/flutter/flutter/issues/12553 was that when the refresh indicator went away, which happened after the avatars had started their image loads but before the avatars had loaded, the DecoratedBoxes, along with the rest of the list, got GlobalKey-reparented, which caused the RenderDecoratedBox objects to unregister from the DecorationImagePainters, but they never re-registered since the whole subtree was in a RepaintBoundary and was therefore not explicitly repainted when the tree got reattached.

This fixes the bug by explicitly requiring any RenderDecoratedBox to repaint when it's reattached. This is probably a little more aggressive than required; we could probably expose a flag on Decoration that says whether or not the onChanged handler will ever be invoked, and only call markNeedsPaint if that's true, but we'll do that if it turns out that there's a performance issue here.

(This patch also introduces a bunch of improved debugging information that I used to track down the bug.)

This allows the scheduler library to depend on the services library
and the painting library to depend on the scheduler library without
the services library having to depend on the scheduler library.

While I was at it I also cleaned up some of the binding logic: the
licenses logic can now be overridden (and the test library does so),
and the image cache can now be overridden as well.

I got tired of drive-by spelling fixes, so I figured I'd just take care of them all at once.

This only corrects errors in the dartdocs, not regular comments, and I skipped any sample code in the dartdocs. It doesn't touch any identifiers in the dartdocs either. No code changes, just comments.

Various improvements (in particular a new painting fuzzer) to the text manual test.

Some additional documentation.

A fix to Stack to remove an LTR bias: make unpositioned children apply "alignment".

Some more debugging information on RichText and Text.

A fix to the flutter tool to not crash when an RPC call throws an exception.

This avoids some code duplication that existed before and will make
further modifications easier.

Unlike FractionalOffset, Alignment uses the center as the zero of the
coordinate system, which makes the RTL math work out much cleaner.

Also, make FractionalOffset into a subclass of Alignment so that clients
can continue to use FractionalOffset.

After all my recent refactorings, some of the names were not really reasonable any more.

To make it cleaner when we RTLify these.