[Extensions] Convert some SyncExtensionFunctions

chrome/browser/speech/extension_api/tts_engine_extension_api.h

Index: chrome/browser/speech/extension_api/tts_engine_extension_api.h
diff --git a/chrome/browser/speech/extension_api/tts_engine_extension_api.h b/chrome/browser/speech/extension_api/tts_engine_extension_api.h
index 441d72f6414188273ed1d5d57c7d62fb22bd25bb..acf042b7fc954a8b8280c2e192ce65cc06ad331b 100644
--- a/chrome/browser/speech/extension_api/tts_engine_extension_api.h
+++ b/chrome/browser/speech/extension_api/tts_engine_extension_api.h
@@ -49,10 +49,11 @@ class TtsExtensionEngine : public TtsEngineDelegate {
 };
 // Hidden/internal extension function used to allow TTS engine extensions
 // to send events back to the client that's calling tts.speak().
-class ExtensionTtsEngineSendTtsEventFunction : public SyncExtensionFunction {
+class ExtensionTtsEngineSendTtsEventFunction
+    : public UIThreadExtensionFunction {
  private:
   ~ExtensionTtsEngineSendTtsEventFunction() override {}
-  bool RunSync() override;
+  ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("ttsEngine.sendTtsEvent", TTSENGINE_SENDTTSEVENT)
 };