Due to inconsistencies in the way browsers handle Exif orientation data,
if a user manually rotates an image within WordPress, set the Exif orientation to
the default (1) so that the image displays with the same rotation/flip in every browser.
Props sanchothefat, triplejumper12, joemcgill, azaozz, markoheijnen, mikeschroder.
Merges [40123] and [40129] to the 4.7 branch.
Fixes#37140. See #14459.
git-svn-id: https://develop.svn.wordpress.org/branches/4.7@40135 602fd350-edb4-49c9-b593-d223f7449a82
