Rm redundant computeSelfDCForParemt

Author: David Ungar

include/swift/AST/ASTScope.h

@@ -847,10 +847,6 @@ class PureFunctionBodyScope final : public AbstractFunctionBodyScope {
   std::string getClassName() const override;
   bool lookupLocalBindings(Optional<bool>,
                            DeclConsumer consumer) const override;
-
-protected:
-  NullablePtr<DeclContext>
-      computeSelfDCForParent(NullablePtr<DeclContext>) const override;
 };
 
 class DefaultArgumentInitializerScope final : public ASTScopeImpl {

lib/AST/ASTScopeLookup.cpp

@@ -597,10 +597,6 @@ MethodBodyScope::computeSelfDCForParent(NullablePtr<DeclContext> selfDC) const {
   assert(!selfDC && "Losing selfDC");
   return decl;
 }
-NullablePtr<DeclContext> PureFunctionBodyScope::computeSelfDCForParent(
-    NullablePtr<DeclContext> selfDC) const {
-  return selfDC;
-}
 
 #pragma mark ifUnknownIsCascadingUseAccordingTo