Remove SetNonBlocking/SetBlocking methods from Socket and add missing close-on-exec

runtime/bin/socket.h

Index: runtime/bin/socket.h
diff --git a/runtime/bin/socket.h b/runtime/bin/socket.h
index ff5444daa585f4546d8c2421e657565bd99e393b..ae59c5aa1d24390da12d77d3dedcbb0c223a660b 100644
--- a/runtime/bin/socket.h
+++ b/runtime/bin/socket.h
@@ -239,8 +239,6 @@ class Socket {
   static int GetType(intptr_t fd);
   static intptr_t GetStdioHandle(intptr_t num);
   static void Close(intptr_t fd);
-  static bool SetNonBlocking(intptr_t fd);
-  static bool SetBlocking(intptr_t fd);
   static bool GetNoDelay(intptr_t fd, bool* enabled);
   static bool SetNoDelay(intptr_t fd, bool enabled);
   static bool GetMulticastLoop(intptr_t fd, intptr_t protocol, bool* enabled);