fix: bind spellchecker receivers correctly in the renderer (#21997)

shell/renderer/browser_exposed_renderer_interfaces.cc

@@ -0,0 +1,39 @@
+// Copyright (c) 2020 Slack Technologies, Inc.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#include "shell/renderer/browser_exposed_renderer_interfaces.h"
+
+#include <utility>
+
+#include "base/bind.h"
+#include "base/threading/sequenced_task_runner_handle.h"
+#include "build/build_config.h"
+#include "electron/buildflags/buildflags.h"
+#include "mojo/public/cpp/bindings/binder_map.h"
+#include "shell/renderer/renderer_client_base.h"
+
+#if BUILDFLAG(ENABLE_BUILTIN_SPELLCHECKER)
+#include "components/spellcheck/renderer/spellcheck.h"
+#endif
+
+namespace {
+#if BUILDFLAG(ENABLE_BUILTIN_SPELLCHECKER)
+void BindSpellChecker(
+    electron::RendererClientBase* client,
+    mojo::PendingReceiver<spellcheck::mojom::SpellChecker> receiver) {
+  if (client->GetSpellCheck())
+    client->GetSpellCheck()->BindReceiver(std::move(receiver));
+}
+#endif
+
+}  // namespace
+
+void ExposeElectronRendererInterfacesToBrowser(
+    electron::RendererClientBase* client,
+    mojo::BinderMap* binders) {
+#if BUILDFLAG(ENABLE_BUILTIN_SPELLCHECKER)
+  binders->Add(base::BindRepeating(&BindSpellChecker, client),
+               base::SequencedTaskRunnerHandle::Get());
+#endif
+}