[dart2js] Clean up wrapper powerset implementation.

This was a very useful experiment to validate that a powerset domain
could answer certain abstract value domain queries more efficiently. Now
that the core ideas have been incorporated directly into the typemasks,
we no longer need to preserve the wrappers.

Change-Id: Ife3df6eeb119783da97eeb721d9c045e5da649ca
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/427020
Commit-Queue: Mayank Patke <[email protected]>
Reviewed-by: Stephen Adams <[email protected]>

Author: fishythefish

pkg/compiler/lib/src/commandline_options.dart

@@ -36,9 +36,6 @@ class Flags {
   static const String experimentalTrackAllocations =
       '--experimental-track-allocations';
 
-  static const String experimentalWrapped = '--experimental-wrapped';
-  static const String experimentalPowersets = '--experimental-powersets';
-
   // Temporary experiment for code generation of locals for frequently used
   // 'this' and constants.
   static const String experimentLocalNames = '--experiment-code-1';

pkg/compiler/lib/src/compiler.dart

@@ -42,12 +42,10 @@ import 'environment.dart';
 import 'inferrer/abstract_value_domain.dart';
 import 'inferrer/abstract_value_strategy.dart';
 import 'inferrer/computable.dart' show ComputableAbstractValueStrategy;
-import 'inferrer/powersets/powersets.dart' show PowersetStrategy;
 import 'inferrer/trivial.dart' show TrivialAbstractValueStrategy;
 import 'inferrer/typemasks/masks.dart' show TypeMaskStrategy;
 import 'inferrer/types.dart'
     show GlobalTypeInferenceResults, GlobalTypeInferenceTask;
-import 'inferrer/wrapped.dart' show WrappedAbstractValueStrategy;
 import 'io/source_information.dart';
 import 'js_backend/codegen_inputs.dart' show CodegenInputs;
 import 'js_backend/enqueuer.dart';
@@ -165,13 +163,6 @@ class Compiler {
         options.useTrivialAbstractValueDomain
             ? const TrivialAbstractValueStrategy()
             : const TypeMaskStrategy();
-    if (options.experimentalWrapped || options.testMode) {
-      abstractValueStrategy = WrappedAbstractValueStrategy(
-        abstractValueStrategy,
-      );
-    } else if (options.experimentalPowersets) {
-      abstractValueStrategy = PowersetStrategy(abstractValueStrategy);
-    }
     if (options.debugGlobalInference) {
       abstractValueStrategy = ComputableAbstractValueStrategy(
         abstractValueStrategy,

pkg/compiler/lib/src/dart2js.dart

@@ -486,8 +486,6 @@ Future<api.CompilationResult> compile(
     _OneOption(Flags.stopAfterProgramSplit, passThrough),
     _OneOption(Flags.disableTypeInference, passThrough),
     _OneOption(Flags.useTrivialAbstractValueDomain, passThrough),
-    _OneOption(Flags.experimentalWrapped, passThrough),
-    _OneOption(Flags.experimentalPowersets, passThrough),
     _OneOption(Flags.disableRtiOptimization, passThrough),
     _OneOption(Flags.terse, passThrough),
     _OneOption('--deferred-map=.+', passThrough),