[tools] Make grokdump.py bind to localhost only.

Minidumps could potentially contain sensitive information, so we
shouldn't be serving them to the world.

R=machenbach@chromium.org

Change-Id: Idb7a3c07c160e82d707a4abb857e098363da3345
Reviewed-on: https://chromium-review.googlesource.com/1015802Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52670}

tools/grokdump.py

@@ -3323,7 +3323,7 @@ DUMP_FILE_RE = re.compile(r"[-_0-9a-zA-Z][-\._0-9a-zA-Z]*\.dmp$")
 class InspectionWebServer(BaseHTTPServer.HTTPServer):
   def __init__(self, port_number, switches, minidump_name):
     BaseHTTPServer.HTTPServer.__init__(
-        self, ('', port_number), InspectionWebHandler)
+        self, ('localhost', port_number), InspectionWebHandler)
     splitpath = os.path.split(minidump_name)
     self.dumppath = splitpath[0]
     self.dumpfilename = splitpath[1]