src: use v8::Isolate::TryGetCurrent() in DumpJavaScriptBacktrace()

It was using Isolate::GetCurrent() which DCHECK on nullptr, even
though what we wanted was to return early if it is nullptr.

PR-URL: #50518
Refs: #50242
Reviewed-By: Vinícius Lourenço Claro Cardoso <[email protected]>
Reviewed-By: Juan José Arboleda <[email protected]>
Reviewed-By: Chengzhong Wu <[email protected]>

Author: joyeecheung

src/debug_utils.cc

@@ -319,7 +319,7 @@ void DumpNativeBacktrace(FILE* fp) {
 }
 
 void DumpJavaScriptBacktrace(FILE* fp) {
-  v8::Isolate* isolate = v8::Isolate::GetCurrent();
+  v8::Isolate* isolate = v8::Isolate::TryGetCurrent();
   if (isolate == nullptr) {
     return;
   }

test/cctest/test_util.cc

@@ -299,3 +299,7 @@ TEST(UtilTest, SPrintF) {
   const std::string with_zero = std::string("a") + '\0' + 'b';
   EXPECT_EQ(SPrintF("%s", with_zero), with_zero);
 }
+
+TEST(UtilTest, DumpJavaScriptStackWithNoIsolate) {
+  node::DumpJavaScriptBacktrace(stderr);
+}