Do not treat lineHeight as a unitless numbers

Match the behavior of react-native for iOS and Android

The browser treats the 'line-height' CSS property as an 'em' value,
while react-native treats it as pixel unit (or device unit, which should
be 'px' for the web), this issue is causing the 'TextInput' component to
be sized incorrectly.

Close #142

src/apis/StyleSheet/normalizeValue.js

@@ -9,7 +9,6 @@ const unitlessNumbers = {
   flexNegative: true,
   fontWeight: true,
   lineClamp: true,
-  lineHeight: true,
   opacity: true,
   order: true,
   orphans: true,