fix(inputs): ignoring input events in IE caused by placeholder changes o...

...r focus/blur on inputs with placeholders

This is my attempt at fixing #8242 as well as the extra placeholder issues with focus/blur. I'm assuming I'm missing a weird test case that still breaks somewhere, but I still think this is an improvement (it definitely is for my use cases).
I tested this with type=number and entering different values (f3 vs f vs 3f all seem different). It seems like validity.badInput doesn't exist in IE11 though and I couldn't find any issues.