AST: Remove ProtocolConformanceRef::getInherited() now that all usages are gone

Author: slavapestov

include/swift/AST/ProtocolConformanceRef.h

@@ -86,11 +86,6 @@ class ProtocolConformanceRef {
   /// Return the protocol requirement.
   ProtocolDecl *getRequirement() const;
 
-  /// Get the inherited conformance corresponding to the given protocol.
-  /// Returns `this` if `parent` is already the same as the protocol this
-  /// conformance represents.
-  ProtocolConformanceRef getInherited(ProtocolDecl *parent) const;
-
   /// Apply a substitution to the conforming type.
   ProtocolConformanceRef subst(Type origType,
                                TypeSubstitutionFn subs,

lib/AST/ProtocolConformance.cpp

@@ -77,30 +77,6 @@ ProtocolDecl *ProtocolConformanceRef::getRequirement() const {
   }
 }
 
-ProtocolConformanceRef
-ProtocolConformanceRef::getInherited(ProtocolDecl *parent) const {
-  assert((getRequirement() == parent ||
-          getRequirement()->inheritsFrom(parent)) &&
-         "not a parent of this protocol");
-  
-  if (parent == getRequirement())
-    return *this;
-  
-  // For an abstract requirement, simply produce a new abstract requirement
-  // for the parent.
-  if (isAbstract()) {
-    return ProtocolConformanceRef(parent);
-  }
-  
-  // Navigate concrete conformances.
-  if (isConcrete()) {
-    return ProtocolConformanceRef(
-      getConcrete()->getInheritedConformance(parent));
-  }
-  
-  llvm_unreachable("unhandled ProtocolConformanceRef");
-}
-
 ProtocolConformanceRef
 ProtocolConformanceRef::subst(Type origType,
                               TypeSubstitutionFn subs,