[inspector] revert fallThrough support for async methods

third_party/inspector_protocol/templates/TypeBuilder_cpp.template

Index: third_party/inspector_protocol/templates/TypeBuilder_cpp.template
diff --git a/third_party/inspector_protocol/templates/TypeBuilder_cpp.template b/third_party/inspector_protocol/templates/TypeBuilder_cpp.template
index 23b6f5399089609af71ac4c5878aae9e171e0a62..efb1c849eca7fe0e3104600631f62b6bb6f33f3b 100644
--- a/third_party/inspector_protocol/templates/TypeBuilder_cpp.template
+++ b/third_party/inspector_protocol/templates/TypeBuilder_cpp.template
@@ -367,7 +367,7 @@ DispatchResponse::Status DispatcherImpl::{{command.name}}(int callId, std::uniqu
       {%- endfor -%}
         {%- if command.parameters -%}, {% endif -%}
         std::move(callback));
-    return lastCallbackFallThrough() ? DispatchResponse::kFallThrough : DispatchResponse::kAsync;
+    return DispatchResponse::kAsync;
     {% endif %}
 }
   {% endfor %}