Remove unneeded width & height checks

[schlessera]

The isTinyNode() method first ensures that all negative or zero values of either width or height are eliminated.

Then, after a check for responsiveness, it checks the width and height again for being a positive value. At his point, this is guaranteed to be true already by the first check, and thus only adds unneeded processing overhead.

This PR removes these unneeded checks, assuming that the initial check is correct.

[CLAassistant]

All committers have signed the CLA.

[patrickkettner]

thanks!