Remove dead code after stablization of NamedTuples

Author: WojciechMazur

compiler/src/dotty/tools/dotc/core/StdNames.scala

@@ -669,7 +669,6 @@ object StdNames {
     val readResolve: N          = "readResolve"
     val zero: N                 = "zero"
     val zip: N                  = "zip"
-    val `++` : N                = "++"
     val nothingRuntimeClass: N  = "scala.runtime.Nothing$"
     val nullRuntimeClass: N     = "scala.runtime.Null$"
 

compiler/src/dotty/tools/dotc/reporting/ErrorMessageID.scala

@@ -217,7 +217,7 @@ enum ErrorMessageID(val isActive: Boolean = true) extends java.lang.Enum[ErrorMe
   case NonNamedArgumentInJavaAnnotationID // errorNumber: 201
   case QuotedTypeMissingID // errorNumber: 202
   case DeprecatedAssignmentSyntaxID // errorNumber: 203
-  case DeprecatedInfixNamedArgumentSyntaxID // errorNumber: 204
+  case DeprecatedInfixNamedArgumentSyntaxID // errorNumber: 204 // no longer emmited
   case GivenSearchPriorityID // errorNumber: 205
   case EnumMayNotBeValueClassesID // errorNumber: 206
   case IllegalUnrollPlacementID // errorNumber: 207

compiler/src/dotty/tools/dotc/reporting/messages.scala

@@ -3370,14 +3370,6 @@ final class DeprecatedAssignmentSyntax(key: Name, value: untpd.Tree)(using Conte
 
   override protected def explain(using Context): String = ""
 
-class DeprecatedInfixNamedArgumentSyntax()(using Context) extends SyntaxMsg(DeprecatedInfixNamedArgumentSyntaxID):
-  def msg(using Context) =
-    i"""Deprecated syntax: infix named arguments lists are deprecated; in the future it would be interpreted as a single name tuple argument.
-       |To avoid this warning, either remove the argument names or use dotted selection."""
-        + Message.rewriteNotice("This", version = SourceVersion.`3.6-migration`)
-
-  def explain(using Context) = ""
-
 class GivenSearchPriorityWarning(
     pt: Type,
     cmp: Int,