Woah, that's an actual HTTP/0.9 site. As such there are no response headers saying content encoding is some format. My _guess_ then is that we are content sniffing it as XML and deciding not to display natively.

It used to work (rendering in real time), and it still works in Firefox.
There are valid use cases where rendering it instead of downloading it is more helpful. And for a stream, I don't know how the browser can properly handle the download (either the download never ends or it misses new stream)

I can't reproduce the issue in 49.0.2623.63 beta (64-bit) on Linux. I've opened http://livebgp.netsec.colostate.edu:50002/ and the XML gets displayed in browser window.

Could you try to reproduce with disabled extensions?

With no extensions,
Windows
Google Chrome	51.0.2664.1 (Official Build) canary (64-bit)
Google Chrome	49.0.2623.64 (Official Build) beta-m (64-bit)
Linux x64
Chromium	48.0.2564.116 (Developer Build) Ubuntu 15.10 (64-bit)

All try to download the url when there is a stream, never ending file "download"

Hrm, it is reproducible today with the same browser, not sure what have changed. 
Per conversation with rdsmith this sounds like a bug and it is confirmed.

Here is excerpt from the net log:

1415298: URL_REQUEST
http://livebgp.netsec.colostate.edu:50002/
Start Time: 2016-03-02 17:37:14.419

t=  9006 [st=     0] +REQUEST_ALIVE  [dt=?]
t=  9006 [st=     0]    DELEGATE_INFO  [dt=1]
                        --> delegate_info = "NavigationResourceThrottle"
t=  9007 [st=     1]    URL_REQUEST_DELEGATE  [dt=0]
t=  9007 [st=     1]    URL_REQUEST_START_JOB  [dt=0]
                        --> load_flags = 37120 (MAIN_FRAME | MAYBE_USER_GESTURE | VERIFY_EV_CERT)
                        --> method = "GET"
                        --> priority = "HIGHEST"
                        --> url = "http://livebgp.netsec.colostate.edu:50002/"
t=  9007 [st=     1]   +URL_REQUEST_START_JOB  [dt=33341]
                        --> load_flags = 37120 (MAIN_FRAME | MAYBE_USER_GESTURE | VERIFY_EV_CERT)
                        --> method = "GET"
                        --> priority = "HIGHEST"
                        --> url = "http://livebgp.netsec.colostate.edu:50002/"
t=  9007 [st=     1]      URL_REQUEST_DELEGATE  [dt=0]
t=  9007 [st=     1]      HTTP_CACHE_GET_BACKEND  [dt=0]
t=  9007 [st=     1]      HTTP_CACHE_OPEN_ENTRY  [dt=0]
                          --> net_error = -2 (ERR_FAILED)
t=  9007 [st=     1]      HTTP_CACHE_CREATE_ENTRY  [dt=0]
t=  9007 [st=     1]      HTTP_CACHE_ADD_TO_ENTRY  [dt=0]
t=  9007 [st=     1]      URL_REQUEST_DELEGATE  [dt=0]
t=  9007 [st=     1]     +HTTP_STREAM_REQUEST  [dt=108]
t=  9007 [st=     1]        HTTP_STREAM_REQUEST_STARTED_JOB
                            --> source_dependency = 1415301 (HTTP_STREAM_JOB)
t=  9115 [st=   109]        HTTP_STREAM_REQUEST_BOUND_TO_JOB
                            --> source_dependency = 1415301 (HTTP_STREAM_JOB)
t=  9115 [st=   109]     -HTTP_STREAM_REQUEST
t=  9115 [st=   109]     +HTTP_TRANSACTION_SEND_REQUEST  [dt=0]
t=  9115 [st=   109]        HTTP_TRANSACTION_SEND_REQUEST_HEADERS
                            --> GET / HTTP/1.1
                                Host: livebgp.netsec.colostate.edu:50002
                                Connection: keep-alive
                                Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
                                Upgrade-Insecure-Requests: 1
                                User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.63 Safari/537.36
                                Accept-Encoding: gzip, deflate, sdch
                                Accept-Language: en-US,en;q=0.8
t=  9115 [st=   109]     -HTTP_TRANSACTION_SEND_REQUEST
t=  9115 [st=   109]     +HTTP_TRANSACTION_READ_HEADERS  [dt=33233]
t=  9115 [st=   109]        HTTP_STREAM_PARSER_READ_HEADERS  [dt=53]
t=  9168 [st=   162]        HTTP_STREAM_PARSER_READ_HEADERS  [dt=33180]
t= 42348 [st= 33342]        HTTP_TRANSACTION_READ_RESPONSE_HEADERS
                            --> HTTP/0.9 200 OK
t= 42348 [st= 33342]     -HTTP_TRANSACTION_READ_HEADERS
t= 42348 [st= 33342]      HTTP_CACHE_WRITE_INFO  [dt=0]
t= 42348 [st= 33342]      HTTP_CACHE_WRITE_DATA  [dt=0]
t= 42348 [st= 33342]      HTTP_CACHE_WRITE_INFO  [dt=0]
t= 42348 [st= 33342]      URL_REQUEST_DELEGATE  [dt=0]
t= 42348 [st= 33342]   -URL_REQUEST_START_JOB
t= 42348 [st= 33342]    URL_REQUEST_DELEGATE  [dt=0]
t= 42348 [st= 33342]    HTTP_TRANSACTION_READ_BODY  [dt=0]
t= 42348 [st= 33342]    HTTP_CACHE_WRITE_DATA  [dt=0]
t= 42348 [st= 33342]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 771
t= 42349 [st= 33343]    URL_REQUEST_SET_PRIORITY
                        --> priority = 0
t= 42349 [st= 33343]   +HTTP_TRANSACTION_READ_BODY  [dt=52]
t= 42349 [st= 33343]      DOWNLOAD_STARTED
                          --> source_dependency = 1415494 (DOWNLOAD)
t= 42401 [st= 33395]   -HTTP_TRANSACTION_READ_BODY
t= 42401 [st= 33395]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t= 42401 [st= 33395]    HTTP_TRANSACTION_READ_BODY  [dt=56953]
t= 99354 [st= 90348]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t= 99354 [st= 90348]    HTTP_TRANSACTION_READ_BODY  [dt=54]
t= 99408 [st= 90402]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t= 99408 [st= 90402]    HTTP_TRANSACTION_READ_BODY  [dt=55953]
t=155361 [st=146355]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t=155361 [st=146355]    HTTP_TRANSACTION_READ_BODY  [dt=1000]
t=156361 [st=147355]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t=156361 [st=147355]    HTTP_TRANSACTION_READ_BODY  [dt=55006]
t=211367 [st=202361]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t=211367 [st=202361]    HTTP_TRANSACTION_READ_BODY  [dt=1000]
t=212367 [st=203361]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t=212367 [st=203361]    HTTP_TRANSACTION_READ_BODY  [dt=56007]
t=268374 [st=259368]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t=268374 [st=259368]    HTTP_TRANSACTION_READ_BODY  [dt=1000]
t=269374 [st=260368]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t=269374 [st=260368]    HTTP_TRANSACTION_READ_BODY  [dt=50006]
t=319380 [st=310374]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t=319380 [st=310374]    HTTP_TRANSACTION_READ_BODY  [dt=54]
t=319434 [st=310428]    URL_REQUEST_JOB_BYTES_READ
                        --> byte_count = 766
t=319434 [st=310428]   +HTTP_TRANSACTION_READ_BODY  [dt=?]
1415494: DOWNLOAD
/usr/local/google/home/mef/Downloads/download (3).crdownload
Start Time: 2016-03-02 17:37:47.762

t=42349 [st= 0] +DOWNLOAD_ITEM_ACTIVE  [dt=?]
                 --> danger_type = "NOT_DANGEROUS"
                 --> file_name = ""
                 --> final_url = "http://livebgp.netsec.colostate.edu:50002/"
                 --> has_user_gesture = false
                 --> id = "8"
                 --> original_url = "http://livebgp.netsec.colostate.edu:50002/"
                 --> start_offset = "0"
                 --> type = "NEW_DOWNLOAD"
t=42349 [st= 0]    DOWNLOAD_URL_REQUEST
                   --> source_dependency = 1415298 (URL_REQUEST)
t=42350 [st= 1]   +DOWNLOAD_FILE_OPENED  [dt=32]
                   --> file_name = "/usr/local/google/home/mef/Downloads/.com.google.Chrome.tlztjX"
                   --> start_offset = "0"
t=42350 [st= 1]      DOWNLOAD_STREAM_DRAINED
                     --> num_buffers = 0
                     --> stream_size = 0
t=42351 [st= 2]      DOWNLOAD_ITEM_UPDATED
                     --> bytes_so_far = "0"
t=42354 [st= 5]     +DOWNLOAD_FILE_RENAMED  [dt=28]
                     --> new_filename = "/usr/local/google/home/mef/Downloads/download (3).crdownload"
                     --> old_filename = "/usr/local/google/home/mef/Downloads/.com.google.Chrome.tlztjX"
t=42354 [st= 5]        DOWNLOAD_FILE_CLOSED
t=42382 [st=33]   -DOWNLOAD_FILE_OPENED
t=42383 [st=34]   +DOWNLOAD_FILE_OPENED  [dt=?]
                   --> file_name = "/usr/local/google/home/mef/Downloads/download (3).crdownload"
                   --> start_offset = "0"
t=42383 [st=34]     -DOWNLOAD_FILE_RENAMED
t=42383 [st=34]      DOWNLOAD_ITEM_RENAMED
                     --> new_filename = "/usr/local/google/home/mef/Downloads/download (3).crdownload"
                     --> old_filename = ""

Here is the netlog.

Deleted: net-internals-log-downloa-instead-of-render.json 353 KB

net-internals-log-downloa-instead-of-render.json 353 KB View Download

I wonder how much we care about HTTP/0.9.

Regardless, the server is sending us non-ASCII characters (Like 0x01).  If we see one of them when we're mime sniffing, we decide it's a binary file and download it.  If we don't, we display it.  This is working as intended.  Whether or not it sends us one varies over time.

Whether or not it sends us a non-ASCII byte varies over time, that is, which explains why it doesn't always repro.