AST: Remove unused method

Author: slavapestov

include/swift/AST/ProtocolConformanceRef.h

@@ -213,11 +213,6 @@ class ProtocolConformanceRef {
   /// Create a canonical conformance from the current one.
   ProtocolConformanceRef getCanonicalConformanceRef() const;
 
-  /// Get any additional requirements that are required for this conformance to
-  /// be satisfied, if they're possible to compute.
-  llvm::Optional<ArrayRef<Requirement>>
-  getConditionalRequirementsIfAvailable() const;
-
   /// Get any additional requirements that are required for this conformance to
   /// be satisfied.
   ArrayRef<Requirement> getConditionalRequirements() const;

lib/AST/ProtocolConformanceRef.cpp

@@ -189,17 +189,6 @@ ProtocolConformanceRef::getWitnessByName(Type type, DeclName name) const {
   return getConcrete()->getWitnessDeclRef(requirement);
 }
 
-llvm::Optional<ArrayRef<Requirement>>
-ProtocolConformanceRef::getConditionalRequirementsIfAvailable() const {
-  if (isConcrete())
-    return getConcrete()->getConditionalRequirementsIfAvailable();
-  else
-    // An abstract conformance is never conditional: any conditionality in the
-    // concrete types that will eventually pass through this at runtime is
-    // completely pre-checked and packaged up.
-    return ArrayRef<Requirement>();
-}
-
 ArrayRef<Requirement>
 ProtocolConformanceRef::getConditionalRequirements() const {
   if (isConcrete())