[model] Remove 'topType' parameter from solveTypeConstraint

The parameter is a remnant of the support for non-Null Safe code. The
removal of the parameter is a step towards the unification between
TypeSchemaEnvironment.solveTypeConstraint in the CFE and
GenericInferrer._chooseTypeFromConstraint in the Analyzer.

Part of #54902

Change-Id: Ie7efe25591eaff5cdd34c4fffdcd772f94040c28
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/422721
Reviewed-by: Paul Berry <[email protected]>
Commit-Queue: Chloe Stefantsova <[email protected]>

Author: chloestefantsova

pkg/front_end/lib/src/type_inference/type_schema_environment.dart

@@ -344,9 +344,7 @@ class TypeSchemaEnvironment extends HierarchyBasedTypeEnvironment
   /// type parameter which means we choose the upper bound rather than the
   /// lower bound for normally covariant type parameters.
   DartType solveTypeConstraint(MergedTypeConstraint constraint,
-      {required DartType topType,
-      bool grounded = false,
-      bool isContravariant = false}) {
+      {bool grounded = false, bool isContravariant = false}) {
     if (!isContravariant) {
       // Prefer the known bound, if any.
       if (isKnown(constraint.lower.unwrapTypeSchemaView())) {
@@ -366,7 +364,7 @@ class TypeSchemaEnvironment extends HierarchyBasedTypeEnvironment
       } else if (constraint.upper is! UnknownType) {
         return grounded
             ? greatestClosure(constraint.upper.unwrapTypeSchemaView(),
-                topType: topType)
+                topType: coreTypes.objectNullableRawType)
             : constraint.upper.unwrapTypeSchemaView();
       } else {
         return const UnknownType();
@@ -387,7 +385,7 @@ class TypeSchemaEnvironment extends HierarchyBasedTypeEnvironment
         // Coverage-ignore-block(suite): Not run.
         return grounded
             ? greatestClosure(constraint.upper.unwrapTypeSchemaView(),
-                topType: topType)
+                topType: coreTypes.objectNullableRawType)
             : constraint.upper.unwrapTypeSchemaView();
       } else if (constraint.lower is! UnknownType) {
         return grounded
@@ -494,9 +492,7 @@ class TypeSchemaEnvironment extends HierarchyBasedTypeEnvironment
     }
 
     return solveTypeConstraint(constraint,
-        topType: coreTypes.objectNullableRawType,
-        grounded: true,
-        isContravariant: isContravariant);
+        grounded: true, isContravariant: isContravariant);
   }
 
   DartType _inferTypeParameterFromContext(DartType? typeFromPreviousInference,
@@ -517,8 +513,7 @@ class TypeSchemaEnvironment extends HierarchyBasedTypeEnvironment
       return typeFromPreviousInference;
     }
 
-    DartType t = solveTypeConstraint(constraint,
-        topType: coreTypes.objectNullableRawType);
+    DartType t = solveTypeConstraint(constraint);
     if (!isKnown(t)) {
       return t;
     }
@@ -553,8 +548,7 @@ class TypeSchemaEnvironment extends HierarchyBasedTypeEnvironment
       constraint = constraint.clone();
       constraint.mergeInTypeSchemaUpper(
           new SharedTypeSchemaView(extendsConstraint), operations);
-      return solveTypeConstraint(constraint,
-          topType: coreTypes.objectNullableRawType);
+      return solveTypeConstraint(constraint);
     }
 
     return t;

pkg/front_end/test/type_inference/type_schema_environment_test_base.dart

@@ -68,7 +68,7 @@ abstract class TypeSchemaEnvironmentTestBase {
       {required bool grounded}) {
     expect(
         typeSchemaEnvironment.solveTypeConstraint(parseConstraint(constraint),
-            topType: coreTypes.objectNullableRawType, grounded: grounded),
+            grounded: grounded),
         parseType(expected));
   }