A new bug was introduced with Safari 7.0 and Webkit on Mac OS X Mavericks that makes the gamma display of sRGB images incorrect. Shadow tones display too dark as it appears Webkit does not use the sRGB tone curve but a straight 2.2 gamma (which is wrong). Safari 6 and before did not have this bug and they displayed sRGB images correctly. I illustrate the issue here: http://lagemaat.blogspot.com/2014/09/color-management-in-safari-is-broken-in.html The image should be identical on mouseover in a correctly color managed browser but as you can see it is not. You can also see this on other test pages such as http://www.gballard.net/psd/go_live_page_profile/embeddedJPEGprofiles.html where you'll see the dark tones shifting considerably blocking up shadows in Safari 7.0 and Webkit nightly.
I think this is probably related to the fact that imageWithColorspace compares the image space to DeviceRGB, which never happens anymore. Ditto for the one in GraphicsLayerCA. But I thought that was OK, too. We'll see.