fix(dom): revert patchEvent optimization, to support IE10+
fix(dom): revert patchEvent optimization, to support IE10+

We had done a memory optimization in commit 0153cea891ec62327cf3a638aa0283e3bb0de156 to avoid
unnecessary function allocations, but it seems that we cant mutate event properties in IE10/IE11, so
in those browsers we experienced an infinite call stack on stopPropagation(). This commit reverts
that optimization.

ntilwalli/cyclejs,ntilwalli/cyclejs,staltz/cycle,cyclejs/cyclejs,cyclejs/cyclejs,usm4n/cyclejs,feliciousx-open-source/cyclejs,ntilwalli/cyclejs,cyclejs/cycle-core,usm4n/cyclejs,staltz/cycle,feliciousx-open-source/cyclejs,ntilwalli/cyclejs,feliciousx-open-source/cyclejs,cyclejs/cyclejs,cyclejs/cyclejs,usm4n/cyclejs,cyclejs/cycle-core,usm4n/cyclejs,feliciousx-open-source/cyclejs