Move signal_blocker to platform and use it by default in TEMP_FAILURE_RETRY.

runtime/bin/stdio_linux.cc

Index: runtime/bin/stdio_linux.cc
diff --git a/runtime/bin/stdio_linux.cc b/runtime/bin/stdio_linux.cc
index f61cc30319bb35b392b646baa5d3ed15113873da..59bca1a8b7eaec264d8d6420bf318fb4d47648e8 100644
--- a/runtime/bin/stdio_linux.cc
+++ b/runtime/bin/stdio_linux.cc
@@ -11,7 +11,6 @@
 
 #include "bin/stdio.h"
 #include "bin/fdutils.h"
-#include "bin/signal_blocker.h"
 
 
 namespace dart {
@@ -66,8 +65,7 @@ void Stdin::SetLineMode(bool enabled) {
 
 bool Stdout::GetTerminalSize(int size[2]) {
   struct winsize w;
-  if (TEMP_FAILURE_RETRY_BLOCK_SIGNALS(
-        ioctl(STDOUT_FILENO, TIOCGWINSZ, &w) != 0)) {
+  if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &w) != 0) {
     return false;
   }
   size[0] = w.ws_col;