Fix A64 after 19635.

src/a64/lithium-codegen-a64.cc

Index: src/a64/lithium-codegen-a64.cc
diff --git a/src/a64/lithium-codegen-a64.cc b/src/a64/lithium-codegen-a64.cc
index 5e48b660d0f44cc7a680ea61cd959da720cbfa33..b358742b52e762158f887ee2e4b58d5509deb958 100644
--- a/src/a64/lithium-codegen-a64.cc
+++ b/src/a64/lithium-codegen-a64.cc
@@ -920,6 +920,8 @@ void LCodeGen::PopulateDeoptimizationData(Handle<Code> code) {
   data->SetInlinedFunctionCount(Smi::FromInt(inlined_function_count_));
   data->SetOptimizationId(Smi::FromInt(info_->optimization_id()));
   if (info_->IsOptimizing()) {
+    // Reference to shared function info does not change between phases.
+    AllowDeferredHandleDereference allow_handle_dereference;
     data->SetSharedFunctionInfo(*info_->shared_info());
   } else {
     data->SetSharedFunctionInfo(Smi::FromInt(0));