Filebrowser read file does not pass correct file length to httpfs

sample file
/user/mapr/blah.txt
has contents "test httpfs"

httpfs-audit.log prints the following when hue filebrowser tries to open that file-

2014-06-18 14:02:27,743 INFO [][mapr:] OPEN [/user/mapr/blah.txt] offset [0] len [-1]

Notice that the length is wrongly set to -1. This causes httpfs to enter the wrong loop here -
https://github.com/cloudera/httpfs/blob/cdh3u6/src/main/java/org/apache/hadoop/lib/wsrs/InputStreamEntity.java#L47

causing httpfs to call the wrong overloaded method IOUtils.copyBytes with int as the 3rd argument. This leads to the whole input stream being copied to the output stream instead of only the bufSize being copied from input stream to output stream.

http://hadoop.apache.org/docs/r2.3.0/api/org/apache/hadoop/io/IOUtils.html#copyBytes(java.io.InputStream, java.io.OutputStream, int, boolean)

With the attached patch, this has been corrected and httpfs-audit.log prints the following -
2014-06-18 14:36:46,796 INFO [][mapr:] OPEN [/user/mapr/blah.txt] offset [0] len [3]