Add corresponding changes in MultiplexExternalSemaSource

Author: dmpolukhin

clang/include/clang/Sema/MultiplexExternalSemaSource.h

@@ -92,6 +92,8 @@ class MultiplexExternalSemaSource : public ExternalSemaSource {
 
   ExtKind hasExternalDefinitions(const Decl *D) override;
 
+  bool wasThisDeclarationADefinition(const FunctionDecl *FD) override;
+
   /// Find all declarations with the given name in the
   /// given context.
   bool FindExternalVisibleDeclsByName(const DeclContext *DC,

clang/lib/Sema/MultiplexExternalSemaSource.cpp

@@ -107,6 +107,14 @@ MultiplexExternalSemaSource::hasExternalDefinitions(const Decl *D) {
   return EK_ReplyHazy;
 }
 
+bool MultiplexExternalSemaSource::wasThisDeclarationADefinition(
+    const FunctionDecl *FD) {
+  for (const auto &S : Sources)
+    if (S->wasThisDeclarationADefinition(FD))
+      return true;
+  return false;
+}
+
 bool MultiplexExternalSemaSource::FindExternalVisibleDeclsByName(
     const DeclContext *DC, DeclarationName Name,
     const DeclContext *OriginalDC) {