Fix a bug with core-input sizes
Fix a bug with core-input sizes

Due to a Chrome change, all core-input elements were force-styled to be
20em wide.  This looked incredibly strange when used with a
paper-input-decorator (as is all over in the code).  This changes the
styling for core-ipnut element below paper-input-decorators so that they
will have the correct size.

Fixes #1878

roceys/uproxy,qida/uproxy,roceys/uproxy,uProxy/uproxy,chinarustin/uproxy,chinarustin/uproxy,roceys/uproxy,qida/uproxy,qida/uproxy,qida/uproxy,roceys/uproxy,dhkong88/uproxy,jpevarnek/uproxy,uProxy/uproxy,jpevarnek/uproxy,MinFu/uproxy,qida/uproxy,MinFu/uproxy,uProxy/uproxy,dhkong88/uproxy,chinarustin/uproxy,dhkong88/uproxy,jpevarnek/uproxy,uProxy/uproxy,dhkong88/uproxy,jpevarnek/uproxy,chinarustin/uproxy,MinFu/uproxy,MinFu/uproxy,jpevarnek/uproxy,chinarustin/uproxy,MinFu/uproxy,roceys/uproxy,uProxy/uproxy,dhkong88/uproxy