Merge pull request #12254 from jckarter/unused-metadata-getGenericPattern

Runtime: Remove unused Metadata::getGenericPattern() method.

Author: jckarter

include/swift/Runtime/Metadata.h

@@ -999,10 +999,6 @@ struct TargetMetadata {
     swift_runtime_unreachable("Unhandled MetadataKind in switch.");
   }
 
-  /// Get the generic metadata pattern from which this generic type instance was
-  /// instantiated, or null if the type is not generic.
-  const TargetGenericMetadata<Runtime> *getGenericPattern() const;
-  
   /// Get the class object for this type if it has one, or return null if the
   /// type is not a class (or not a class with a class object).
   const TargetClassMetadata<Runtime> *getClassObject() const;

stdlib/public/runtime/Metadata.cpp

@@ -2420,13 +2420,6 @@ swift::swift_getForeignTypeMetadata(ForeignTypeMetadata *nonUnique) {
 /*** Other metadata routines ***********************************************/
 /***************************************************************************/
 
-template<> const GenericMetadata *
-Metadata::getGenericPattern() const {
-  if (const auto *ntd = getNominalTypeDescriptor())
-    return ntd->getGenericMetadataPattern();
-  return nullptr;
-}
-
 template<> const ClassMetadata *
 Metadata::getClassObject() const {
   switch (getKind()) {