[all] add fuchsia.{net.NameLookup,posix.socket.Provider} (flutter/engine#9546)

These services will replace fuchsia.net.SocketProvider.

Note that dart_{aot,jit}_product_runner.cmx were invalid before this
change. I'm not sure how that was allowed to happen.

engine/src/flutter/shell/platform/fuchsia/dart/meta/dart_aot_product_runner.cmx

@@ -4,7 +4,7 @@
     },
     "sandbox": {
         "features": [
-            "root-ssl-certificates"
+            "root-ssl-certificates",
             "deprecated-ambient-replace-as-executable"
         ],
         "services": [

engine/src/flutter/shell/platform/fuchsia/dart/meta/dart_jit_product_runner.cmx

@@ -4,7 +4,7 @@
     },
     "sandbox": {
         "features": [
-            "root-ssl-certificates"
+            "root-ssl-certificates",
             "deprecated-ambient-replace-as-executable"
         ],
         "services": [