[CS] Tweak addExplicitConversionConstraint slightly (#30687)

[CS] Tweak `addExplicitConversionConstraint` slightly

Author: hamishknight

lib/Sema/CSGen.cpp

@@ -2978,8 +2978,8 @@ namespace {
 
       // Add a conversion constraint for the direct conversion between
       // types.
-      CS.addExplicitConversionConstraint(fromType, toType,
-                                         /*allowFixes=*/true, locator);
+      CS.addExplicitConversionConstraint(fromType, toType, RememberChoice,
+                                         locator);
 
       // If the result type was declared IUO, add a disjunction for
       // bindings for the result of the coercion.

lib/Sema/CSSimplify.cpp

@@ -7291,13 +7291,13 @@ ConstraintSystem::simplifyBridgingConstraint(Type type1,
   if (auto fromKeyValue = isDictionaryType(unwrappedFromType)) {
     if (auto toKeyValue = isDictionaryType(unwrappedToType)) {
       addExplicitConversionConstraint(fromKeyValue->first, toKeyValue->first,
-                                      /*allowFixes=*/false,
+                                      ForgetChoice,
                                       locator.withPathElement(
                                         LocatorPathElt::GenericArgument(0)));
       addExplicitConversionConstraint(fromKeyValue->second, toKeyValue->second,
-                                      /*allowFixes=*/false,
+                                      ForgetChoice,
                                       locator.withPathElement(
-                                        LocatorPathElt::GenericArgument(0)));
+                                        LocatorPathElt::GenericArgument(1)));
       countOptionalInjections();
       return SolutionKind::Solved;
     }
@@ -9701,9 +9701,8 @@ void ConstraintSystem::addFixConstraint(ConstraintFix *fix, ConstraintKind kind,
 }
 
 void ConstraintSystem::addExplicitConversionConstraint(
-                                           Type fromType, Type toType,
-                                           bool allowFixes,
-                                           ConstraintLocatorBuilder locator) {
+    Type fromType, Type toType, RememberChoice_t rememberChoice,
+    ConstraintLocatorBuilder locator) {
   SmallVector<Constraint *, 3> constraints;
 
   auto locatorPtr = getConstraintLocator(locator);
@@ -9721,9 +9720,7 @@ void ConstraintSystem::addExplicitConversionConstraint(
                      fromType, toType, locatorPtr);
   constraints.push_back(bridgingConstraint);
 
-  addDisjunctionConstraint(constraints, locator,
-                           allowFixes ? RememberChoice
-                                      : ForgetChoice);
+  addDisjunctionConstraint(constraints, locator, rememberChoice);
 }
 
 ConstraintSystem::SolutionKind

lib/Sema/ConstraintSystem.h

@@ -2855,8 +2855,14 @@ class ConstraintSystem {
   }
 
   /// Add an explicit conversion constraint (e.g., \c 'x as T').
+  ///
+  /// \param fromType The type of the expression being converted.
+  /// \param toType The type to convert to.
+  /// \param rememberChoice Whether the conversion disjunction should record its
+  /// choice.
+  /// \param locator The locator.
   void addExplicitConversionConstraint(Type fromType, Type toType,
-                                       bool allowFixes,
+                                       RememberChoice_t rememberChoice,
                                        ConstraintLocatorBuilder locator);
 
   /// Add a disjunction constraint.