This is the correct metric to report for compilation time benchmarks rather
than RunTime. Rename the 'gen_snapshot' value to merely 'snapshot' for
backwards compatibility and overall simplicity.

This change simplifies Dart's benchmarking of Flutter by making it easier to
adopt --report-timings (made for Dart to use), which makes the benchmarks
much more robust.

* Support release/debug flavors of flutter_patched_sdk

* Use [anyNamed] instead of [any] for mocking named arguments

* Fix use of local engine in release mode

This flag makes flutter build aot report timings for substeps (e.g.
frontend compilation and gen_snapshot) in a machine readable form.

This command line argument has already been removed in the main
Dart repository, so building flutter with the latest dart fails.

This time, also update the tests to avoid the checks for a package
path on snapshot generation.

This reverts commit 1c021506.

The pre-commit tests never actually ran, so it looked green when it wasn't. This breaks 16 tests that depend on the argument existing, even though it isn't actually used.

This command line argument has already been removed in the main
Dart repository, so building flutter with the latest dart fails.

This reverts commit 965dc52e as performance gains seems to outweigh compressed apk size increase.

This PR aims at several things:

1. Use pub_semver to check a version in pubspec.yaml meets the requirements specified in https://semver.org/.
2. Don't limit build-number/build-name as a fixed format. Instead, validate it according to the target(ios/android).
3. Make sure that build-number/build-name are always validated no matter it's specified by the `flutter command` or version in pubspec.yaml.

Fixes #27589

Issue #27250

Also, remove old flags.

Ensure that cached dill files for builds with --track-widget-creation
always have .track. in the file name to avoid mixing transformed and
untransformed kernel files.

Also includes
  * Updates to affected tests
  * Change flutter_tools to pass package URIs to the Dart front end
    instead of filesystem paths

This reverts commit b07d986f.

Eliminates the --snapshot and --depfile parameters from the flutter
bundle command. The snapshot parameter is unused in Dart 2 -- code is
built to kernel .dill files and for profile/release builds, then AOT
compiled.

While depfiles are still used in Dart 2 (e.g. by the kernel compiler),
there are enough assumptions in the code that they lie in the default
location (e.g. in the Gradle build) and no reasons to support
user-cusomisation that it makes sense to eliminate the --depfile option
as well, and always use the default location.

This commit also renames 'depFilePath' to 'depfilePath' for consistency
across the codebase.

This also involves switching from Core JIT to App JIT snapshot, and replacing per-isolate VM snapshot with the shared VM snapshot.

For now there is no separate update bundle file, as the generated update gets packaged directly into the APK for testing purposes.

* Improve documentation and clean up code.

* Remove "Note that".

The phrase "note that" is basically meaningless as a prefix to an
otherwise fine sentence.

* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

This tickled a bug in KernelCompiler.compile() where the fingerprinter
doesn't include the outputFilePath in its list of dependencies. As such,
if the output .dill file is missing or corrupted, the fingerprint still
matches and re-compile is skipped, even though it shouldn't be. I'll fix
that in a followup, then look at how this triggered that issue. My
hypothesis is that that it's due to the aot kernel compile and bundle
kernel compile have separate output directories for the .dill files
(build/ vs build/aot) but the same output directory for the associated
depfiles (due to this patch).

This reverts commit 43a106e9.

The --snapshot argument was only necessary in Dart 1. The --depfile
argument was only used in Dart 2 mode to pass to the kernel compiler,
but was inconsistent with the 'build aot' command, where the depfile was
always set to build/kernel_compile.d.

This patch updates 'build bundle' to emit the depfile to a location
consistent with the 'build aot' command; since it's not intended to be
user-configurable and flutter.gradle hardcodes the location to
build/kernel_compile.d either way, this patch also eliminates the
ability to configure the filename altogether.

Script snapshots were only every used in Dart 1 mode, which is no longer
supported.

Fixes the pattern for some TODOs to match our style guide.

(Also, a couple of minor code order fixes.)