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

runtime/bin/file_system_watcher_linux.cc

Index: runtime/bin/file_system_watcher_linux.cc
diff --git a/runtime/bin/file_system_watcher_linux.cc b/runtime/bin/file_system_watcher_linux.cc
index 2a5fee547c062276d7d36b5415d2b7c24a72a0f7..3a868ee92ae8f97540db90e476aacbcdb83fbf75 100644
--- a/runtime/bin/file_system_watcher_linux.cc
+++ b/runtime/bin/file_system_watcher_linux.cc
@@ -23,7 +23,7 @@ bool FileSystemWatcher::IsSupported() {
 
 
 intptr_t FileSystemWatcher::Init() {
-  int id = TEMP_FAILURE_RETRY(inotify_init1(IN_CLOEXEC));
+  int id = inotify_init1(IN_CLOEXEC);
   if (id < 0) return -1;
   // Some systems dosn't support setting this as non-blocking. Since watching
   // internals are kept away from the user, we know it's possible to continue,
@@ -47,7 +47,7 @@ intptr_t FileSystemWatcher::WatchPath(intptr_t id,
   if (events & kModifyContent) list_events |= IN_CLOSE_WRITE | IN_ATTRIB;
   if (events & kDelete) list_events |= IN_DELETE;
   if (events & kMove) list_events |= IN_MOVE;
-  int path_id = TEMP_FAILURE_RETRY(inotify_add_watch(id, path, list_events));
+  int path_id = inotify_add_watch(id, path, list_events);
   if (path_id < 0) {
     return -1;
   }
@@ -56,7 +56,7 @@ intptr_t FileSystemWatcher::WatchPath(intptr_t id,
 
 
 void FileSystemWatcher::UnwatchPath(intptr_t id, intptr_t path_id) {
-  VOID_TEMP_FAILURE_RETRY(inotify_rm_watch(id, path_id));
+  inotify_rm_watch(id, path_id);
 }