I copy this from my FeatureLayer.
{
"value" : "R1-1",
"label" : "R1-1",
"description" : "",
"symbol" :
{
"type" : "esriPMS",
"url" : "D94E722A",
"imageData" : "iVBORw0KGgoAAAANSUhEUgAAACgAAAAoCAYAAACM/rhtAAAAAXNSR0IB2cksfwAAAAlwSFlzAAAOxAAADsQBlSsOGwAABSZJREFUWIXt2GtQlFUcx/HveZbdVRACR2zykq6Y5tRYDgOMvNEaw0yiTMtmrBTNcUSrcUYQ1LwtpalZzfjCqabSGhrvCngrvOEFgRzzMjYqi1YKwnKTZReW3T2nF66bTAK7gNU4/t6e/znnM+c55zy7TxD/8wT914D28hDY2TyYQKWUzn7jZnRT+fVQP7tc7BUTU96RuQIGKqWCGisrd137yDy++dhJv/p0Gzum2VpQEBs5cuTZ+wpUSgU1Wa27S5ctf8lfHEDTgTyDVYiiqsLCuF5xcb/eF6AXl126bPm4QHA+5P6fDZVCFFqLi2MjY2L8Xkm/gEqpoKaqquzS5eZxzvwTAeN8yH0/GaxCK6o5fTq2Z3S0X8h2gUopvbO6Ort0hflF59FjHcb5kHv3Gyo0UVRz5kxczxEj2n3cbQKVUnpnTU2OZUXmWOfh/E7j7qQxd5+hQojCmnPn4noOH94mslWgF5drMZsTnIeOdBnOh8zZa6j0A9nWCm6zmM0JzrzbOJ2pP0GPD8R54iS4PYiQYNDpfMXK4QC3BwDjmNEou4PmgiJfuwjzXpkeD8ruAMCRvcdQ1SPklFIqSghxI1Bg0h1c78xl9ElMROh0OGtrubpqNUM/zkTcBfwj60eqV66m94ol9J0wAeXxYFm3DtumLEImT2LI4kW+WpfNxu8bNmDblIXz0mUjMAIIGAiAPvpZ+iQl8WdWFrbjJxiQvoC+s2Zy/vXJ9Bg9ikHvv8eFacm4S68BEPnc85Tt2UP3fv3onZSEbVOWb6wrK1ehpCQycTz9Z8zg4l1traVdoBYRjhCC5us3aD5egGXmLERYGJ4rFjyxMQB4yspRtXXookwYwh/h1pGjuJ5+ir6TJrUYy567F1VvQxfcnYh58xBGY+eBzrwj1F++TFTqfGrHJlD+5Ve0dlHrnxgMgOvqNdx9HiMoOBiC/t4GIiIcERFOaHQ0LpsN5XR2HghgmTiZiA/m8ujLiQz7/DNKVq/BvnnbP+p0IT0AkJVWlMsFQiCCg33tz+RmA6Ck5PqWrf5M7f+rrvaL9dR9/Q1RP2yk3/RkLt0D6KmvA26fWGHshvJ4UPU2X3vJmjUol5umi7/hPnu+a4CG2Gh6vTWFmys/QZZXYN23H9PcOffcPy7vQdEPMqGPjKT5LhxAw66cFuAuAUpHI71HjcJVU0v1t98RHj+S5lu37rl/PJaruBsaCI2Pp8ewJ2kqKwsI0yGg+8JFynNy6PvqK/Sb+Bpuh4Nr69e3Wm89dpz+b06+fQ+u/fT+AwEqFi+jauP3GIYOwVn8C7LCCkDD5q2cPXQYWV7hq72ZlkHdwTxkXT3NhcUA2Lfv5Gz+sYAfb7vAkDcmYt+yHQDPFQuNVywtC9yeFrg7aTpw0K86gJD4+I4BlVJro9JS51uUwr51R5uDdDRh7yYzIHlaMdDqT6VWgZqmpUopVdSCtFSLVNi37+xa3IxpmFJmF2l6/QtCiPqAgV5kmpRSRqWnLShREseO3V2Em4opZXahptcntIVrF+hFpksp1eCM9PQSpXDszO4cbvpUTCkppzSDIUEI0e6p8esUa5qWIaWUgxdmLCxRCseunA7i3sGUMttvnN9AL3KRlFINXpixqAQCRoYlv40pJaVAMxoThBAN/vYL6H+xpmmLvSv5YYlSOHbn+tUvdOoUBs6Zc1IzGscGggsY6EUukVKqoZnmJWSa/e2WD7wkhLAHOl+Hvs1omrYUWNqRvoHmwfy69W/mIbCzeQjsbP4CD1NBYhK6YDwAAAAASUVORK5CYII=",
"contentType" : "image/png",
"color" : null,
"width" : 30,
"height" : 30,
"angle" : 0,
"xoffset" : 0,
"yoffset" : 0
}
},
I also opened the original MXD document and the symbols are rotate plus I attached the service layer to ArcMap and the symbols show up rotated there too.