When pasting both image data and text into Chrome, use only the text
Summary: Fixes T5437. This actual behavior is debateable but this is the one that seems simplest and most sensible.
Test Plan: Copied some cells from Numbers, pasted them into a remarkup box in Chrome, got just the text.
Reviewers: btrahan, chad
Reviewed By: chad
Maniphest Tasks: T5437
Differential Revision: https://secure.phabricator.com/D9647