path: improve posixSplitPath performance

Instead of slicing the first element off of the matches, shift and then return. This improves performance of the following path functions: - basename: 18-20% - extname: 60-70% - dirname: 18-20% - parse: 20-25% PR-URL: #3034 Reviewed-By: Brian White <[email protected]> Reviewed-By: Sakthipriyan Vairamani <[email protected]>

Author: evanlucas

lib/path.js

@@ -408,7 +408,9 @@ var posix ={};
 
 
 functionposixSplitPath(filename){
-returnsplitPathRe.exec(filename).slice(1);
+constout=splitPathRe.exec(filename);
+out.shift();
+returnout;
 }