Add new overloads of existing methods of Math in Java 9.
Add new overloads of existing methods of Math in Java 9.

They are needed so that existing code still links when compiled on
JDK 9.

SebsLittleHelpers/scala-js,sjrd/scala-js,scala-js/scala-js,gzm0/scala-js,SebsLittleHelpers/scala-js,gzm0/scala-js,nicolasstucki/scala-js,sjrd/scala-js,scala-js/scala-js,sjrd/scala-js,nicolasstucki/scala-js,scala-js/scala-js