Add wgFileCanRotate to JsConfigVars

wgFileCanRotate is used in mw.UploadWizardUpload.js

wgFileCanRotate gets removed from ResourceLoaderStartUpModule.php by
Iff6a952c8f4f21c0e27bd6b4191f3b0b453eec03.

Change-Id: I3c50b56e6a11742cfc1c02d3d8dbeb0c151b0e91