Fix MSAN error on arm64 bot.

src/api.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/api.h"
 
 #include <string.h>  // For memcpy, strlen.
 #ifdef V8_USE_ADDRESS_SANITIZER
 #include <sanitizer/asan_interface.h>
 #endif  // V8_USE_ADDRESS_SANITIZER
@@ skipping 7532 matching lines @@
 }
 
 void Isolate::GetStackSample(const RegisterState& state, void** frames,
                              size_t frames_limit, SampleInfo* sample_info) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
 #if defined(USE_SIMULATOR)
   RegisterState regs;
   regs.pc = state.pc;
   regs.sp = state.sp;
   regs.fp = state.fp;
-  i::SimulatorHelper::FillRegisters(isolate, &regs);
+  if (!i::SimulatorHelper::FillRegisters(isolate, &regs)) {
+    sample_info->frames_count = 0;
+    sample_info->vm_state = OTHER;
+    sample_info->external_callback_entry = nullptr;
+    return;
+  }
 #else
   const RegisterState& regs = state;
 #endif
   i::TickSample::GetStackSample(isolate, regs, i::TickSample::kSkipCEntryFrame,
                                 frames, frames_limit, sample_info);
 }
 
 size_t Isolate::NumberOfPhantomHandleResetsSinceLastCall() {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
   size_t result = isolate->global_handles()->NumberOfPhantomHandleResets();
@@ skipping 1335 matching lines @@
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 }  // namespace internal
 }  // namespace v8