[Cherry Pick fac3fa0c20e0d5f04a6f6e8f7056fde3801263c3] Editor: IE 11 no longer supports `document.selection`, in favor of `window.getSelection`.
Merge branch 'patch/fix-rte-on-ie11' into release/3.14.1-1-odl

* patch/fix-rte-on-ie11:
  [Cherry Pick fac3fa0c20e0d5f04a6f6e8f7056fde3801263c3] Editor: IE 11 no longer supports `document.selection`, in favor of `window.getSelection`.