[Experimental] Supporting OOPIF printing

content/public/app/mojo/content_utility_manifest.json

 {
   "name": "content_utility",
   "display_name": "Content (utility process)",
   "interface_provider_specs": {
     "service_manager:connector": {
       "provides": {
         "browser": [
           "IPC::mojom::ChannelBootstrap",
           "service_manager::mojom::ServiceFactory"
         ],
         "service_manager:service_factory": [
           "service_manager::mojom::ServiceFactory"
+        ],
+        "discardable_memory": [
+          "discardable_memory::mojom::DiscardableSharedMemoryManager"
         ]
       },
       "requires": {
         "device": [
           "device:power_monitor",
           "device:time_zone_monitor"
         ]
       }
     }
   }
 }