Revert part of D39268920

Summary:
This task has been created T131775291 that blames D39268920 (facebook@f1c1f81). I reverted part of the changes and added the support of capital letters for the font weight. It should make the test pass.

However, I am a bit puzzled: I tried to change the title of the `GemstoneTitleBar` and the test was not showing the changed value. I think I'm missing something.

Changelog: [Internal]

Reviewed By: GijsWeterings

Differential Revision: D39478951

fbshipit-source-id: d3e28336fe52c5c58b49872c3f5b6e63e1e37ca5

Libraries/StyleSheet/StyleSheetTypes.js

@@ -613,7 +613,18 @@ export type ____FontWeight_Internal =
   | 'condensedBold'
   | 'condensed'
   | 'heavy'
-  | 'black';
+  | 'black'
+  | 'Ultralight'
+  | 'Thin'
+  | 'Light'
+  | 'Normal'
+  | 'Medium'
+  | 'Semibold'
+  | 'Bold'
+  | 'Condensed'
+  | 'CondensedBold'
+  | 'Heavy'
+  | 'Black';
 
 export type ____FontVariantArray_Internal = $ReadOnlyArray<
   | 'small-caps'