[vm] Always inline List.generate
[vm] Always inline List.generate

Micro-benchmark creating 100,000 lists using

  List<int>.generate(1000, (int x) => x, growable: false);

in AOT mode on x64: 1006ms -> 311ms

Flutter gallery size in release mode on armv7
+6890 bytes (+0.0778%).

Flutter gallery size in release mode with size optimizations on armv7
+9303 bytes (+0.1222%).

Issue: https://github.com/dart-lang/sdk/issues/42283
Change-Id: I283c4dbaf90396dfbefdb59c2cd346def88e186a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/151082
Reviewed-by: Régis Crelier <c2bf536a10d9f2530c38e4e8da517718be8c39ce@google.com>
Commit-Queue: Alexander Markov <239e774fd29abc1267878f57afe1a8a03e0ca887@google.com>

dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk