[clang] fix source range computation for DeducedTemplateSpecializationType (llvm#153646)

This was a regression introduced in
llvm#147835

Since this regression was never released, there are no release notes.

Fixes llvm#153540

Author: mizvekov

clang/include/clang/AST/TypeLoc.h

@@ -2519,6 +2519,15 @@ class DeducedTemplateSpecializationTypeLoc
     getLocalData()->QualifierData = QualifierLoc.getOpaqueData();
   }
 
+  SourceRange getLocalSourceRange() const {
+    SourceLocation BeginLoc = getElaboratedKeywordLoc();
+    if (BeginLoc.isInvalid())
+      BeginLoc = getQualifierLoc().getBeginLoc();
+    if (BeginLoc.isInvalid())
+      BeginLoc = getNameLoc();
+    return {BeginLoc, getNameLoc()};
+  }
+
   void initializeLocal(ASTContext &Context, SourceLocation Loc);
 };