Remove timing limitation of SetOption invocation for PPAPI sockets.

Currently PPAPI has timing limitation for sockets' SetOption.
NODELAY, and BROADCAST need to be before Connect() or Bind(),
while RCVBUF_SIZE and SNFBUF_SIZE need to be after it.

This CL removes such a limitation.
Along with the change, pepper_udp_socket_message_filter starts to use UDPSocket instead of UDPServerSocket, so that the implementation direction gets closer to TCP message filter a little bit.

BUG=425563, 420697
TEST=Ran trybots.

Review URL: https://codereview.chromium.org/690903002

Cr-Commit-Position: refs/heads/master@{#307867}
diff --git a/ppapi/proxy/udp_socket_resource.h b/ppapi/proxy/udp_socket_resource.h
index e0d099a..81aad26 100644
--- a/ppapi/proxy/udp_socket_resource.h
+++ b/ppapi/proxy/udp_socket_resource.h
@@ -36,6 +36,10 @@
                          PP_Resource addr,
                          scoped_refptr<TrackedCallback> callback) override;
   virtual void Close() override;
+  virtual int32_t SetOption1_0(
+      PP_UDPSocket_Option name,
+      const PP_Var& value,
+      scoped_refptr<TrackedCallback> callback) override;
   virtual int32_t SetOption(PP_UDPSocket_Option name,
                             const PP_Var& value,
                             scoped_refptr<TrackedCallback> callback) override;