webkit-fake-url: URL scheme

[1] Bug 49141 – use data uri instead of webkit-fake-url for contentEditable ( ( 版)) <https://bugs.webkit.org/show_bug.cgi?id=49141>

[2] Clipboard API Improvements | WebKit () <https://webkit.org/blog/8170/clipboard-api-improvements/>

Previously, sub-resources (such as image files in pasted content) used URLs of the form webkit-fake-url://<filename> where <filename> is the filename of the sub-resource. Because this is not a standard protocol the website can access, the pasted images’ data were inaccessible to websites.