Fix an issue that share menu is not work if there was no selected text

Fix an issue that share menu is not work if there was no selected text

[Title] Fix an issue that share menu is not work if there was no selected text
[Issue#] N_SE-8599
[Problem] Share menu is not work in url field unless selected text is in the url
[Cause] Not considered of a case of empty selected text
[Solution] Share URL if no selected text in url field but still not support sha$
[Team] Browser UI
[Developer] junghwan kang (junghwan.kang)

[Request] N/A

Change-Id: I6eb1ebd40f7876982e49eed549039c18f7f521be