Editor isn't resized after execCommand "inserthtml"

[guest]

When using execCommand("inserthtml", someHtmlString) from a script, the editor doesn't resize until another event occurs in the editor.

The last two lines of execCommand are:

this.onDisplayChanged(); return returnValue;

onDisplayChanged is "connect"ed to _updateHeight, but this code isn't being reached because of return statements earlier in execCommand. Part of execCommand sets returnValue, and part of it uses return statements. It looks like it is all supposed to set returnValue.

[liucougar]

(In [9993]) fixes #4029: ensure all commands triggers ondisplaychanged()