fix: catch ELOOP

fs.realpath has been optimized to utilize `uv_fs_realpath()`, a new api
in libuv. The libuv api has slightly different behavior. There are two
particular issues that are causing problems for glob

* `ev_fs_realpath()` throwing before `fs.readdir` ELOOP
* The removal of the cache

In the past glob was relying on `fs.readdir` to throw when handling
recursive symbolically linked directories. It is now possible that the
call to libuv can throw before. The behavior is currently different on
osx and linux causing the test suite to fail on all of the flavors of
linux we are running in CI.

This commit adds an extra check for 'ELOOP' and sets appropriately.

The commit includes an extra check to make sure that `real` is truthy
Without that extra check the test suite was reporting garbage data in the results.
This was only happening with the async implementation.

This commit has not done anything regarding the removal of the cache
As long as the cache doesn't include a value called "encoding"
everything will be fine.

There has not been any benchmarking done on this change.

ref: libuv/libuv#531
ref: nodejs/node#3594

glob.js

@@ -237,6 +237,9 @@ Glob.prototype._realpathSet = function (index, cb) {
         set[real] = true
       else if (er.syscall === 'stat')
         set[p] = true
+      else if (er.code === 'ELOOP') {
+        if (real) set[real] = true
+      }
       else
         self.emit('error', er) // srsly wtf right here
 

sync.js

@@ -62,6 +62,9 @@ GlobSync.prototype._finish = function () {
         } catch (er) {
           if (er.syscall === 'stat')
             set[self._makeAbs(p)] = true
+          else if (er.code === 'ELOOP') {
+            if (real) set[real] = true
+          }
           else
             throw er
         }