String with whitespace causes uniteless css warning

[jonashaefele]

What is the current behavior?
Assigning a style object with content: " " to component results in a unitless CSS warning:

warning: a divtag (owner:unknown) was passed a numeric string value for CSS property content(value: ) which will be treated as a unitless number in a future version of React.

Demo Fiddle with content: ""
https://jsfiddle.net/oktkht5g/

Demo fiddle with content: ""
https://jsfiddle.net/o014p2mf/1/

What is the expected behavior?
Only throw warnings for CSS properties that need them. content could be any string or one of the following values:

normal | none | [ <string> | <uri> | <counter> | attr() | open-quote | close-quote | no-open-quote | no-close-quote ]+

Which versions of React
Tested in React 15.1.0

[alexzherdev]

Proposing a fix in #6928.

[jonashaefele]

Thanks!

[jimfb]

Fixed in #6899.