Apply RAII

Co-authored-by: Mehdi Amini <joker.eph@gmail.com>

Author: j2kun

mlir/lib/Rewrite/PatternApplicator.cpp

@@ -211,10 +211,11 @@ LogicalResult PatternApplicator::matchAndRewrite(
 
 #ifndef NDEBUG
             OpBuilder::Listener *oldListener = rewriter.getListener();
-            RewriterBase::CatalogingListener *catalogingListener =
-                new RewriterBase::CatalogingListener(oldListener,
+            auto catalogingListener =
+                std::make_unique<RewriterBase::CatalogingListener>(oldListener,
                                                      pattern->getDebugName());
-            rewriter.setListener(catalogingListener);
+            rewriter.setListener(catalogingListener.get());
+            llvm::make_scope_exit([&] { rewriter.setListener(oldListener); };
 #endif
             result = pattern->matchAndRewrite(op, rewriter);
             LLVM_DEBUG(llvm::dbgs()