[inspector][fuzzer] Handle termination while creating context

This happens flakily on ClusterFuzz. It might not be relevant for users,
but fixing it will allow ClusterFuzz to make more progress.

R=szuend@chromium.org

Bug: chromium:1190898
Change-Id: I7d0b705ff66e80e17ffc322b5d5fd5eb252d5965
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2778174Reviewed-by: Simon Zünd <szuend@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73596}

test/inspector/inspector-test.cc

@@ -322,8 +322,9 @@ class UtilsExtension : public IsolateData::SetupGlobalTask {
         ToVector(args.GetIsolate(), args[1].As<v8::String>());
 
     RunSyncTask(backend_runner_, [&context_group_id, name](IsolateData* data) {
-      data->CreateContext(context_group_id,
-                          v8_inspector::StringView(name.data(), name.size()));
+      CHECK(data->CreateContext(
+          context_group_id,
+          v8_inspector::StringView(name.data(), name.size())));
     });
   }
 

test/inspector/isolate-data.cc

@@ -72,11 +72,14 @@ IsolateData* IsolateData::FromContext(v8::Local<v8::Context> context) {
 
 int IsolateData::CreateContextGroup() {
   int context_group_id = ++last_context_group_id_;
-  CreateContext(context_group_id, v8_inspector::StringView());
+  if (!CreateContext(context_group_id, v8_inspector::StringView())) {
+    DCHECK(isolate_->IsExecutionTerminating());
+    return -1;
+  }
   return context_group_id;
 }
 
-void IsolateData::CreateContext(int context_group_id,
+bool IsolateData::CreateContext(int context_group_id,
                                 v8_inspector::StringView name) {
   v8::HandleScope handle_scope(isolate_.get());
   v8::Local<v8::ObjectTemplate> global_template =
@@ -87,12 +90,14 @@ void IsolateData::CreateContext(int context_group_id,
   }
   v8::Local<v8::Context> context =
       v8::Context::New(isolate_.get(), nullptr, global_template);
+  if (context.IsEmpty()) return false;
   context->SetAlignedPointerInEmbedderData(kIsolateDataIndex, this);
   // Should be 2-byte aligned.
   context->SetAlignedPointerInEmbedderData(
       kContextGroupIdIndex, reinterpret_cast<void*>(context_group_id * 2));
   contexts_[context_group_id].emplace_back(isolate_.get(), context);
   if (inspector_) FireContextCreated(context, context_group_id, name);
+  return true;
 }
 
 v8::Local<v8::Context> IsolateData::GetDefaultContext(int context_group_id) {

test/inspector/isolate-data.h

@@ -50,7 +50,8 @@ class IsolateData : public v8_inspector::V8InspectorClient {
 
   // Setting things up.
   int CreateContextGroup();
-  void CreateContext(int context_group_id, v8_inspector::StringView name);
+  V8_NODISCARD bool CreateContext(int context_group_id,
+                                  v8_inspector::StringView name);
   void ResetContextGroup(int context_group_id);
   v8::Local<v8::Context> GetDefaultContext(int context_group_id);
   int GetContextGroupId(v8::Local<v8::Context> context);