Info window balloons do not show content in Earth API Plugin

[GoogleCodeExporter]

Steps to reproduce the problem:

1.  Publish a GEB map
2.  Load the map in a custom web app using the Earth API Plugin
3.  Click on an object

Observed behavior:

The balloon is either empty, or displays content such as 'ftid  0:...'

Expected behavior:

Balloon content is rendered consistent with Google Earth Enterprise Client 
(EC), or 2D Maps loaded via MapDataLayer.

Workaround:

Please refer to the following (public) example:

http://geohost.apps-tses.com:8080/side_db.html

As demonstrated in the source code, it will be necessary to copy and import the 
following two files in your (client-side) map page:

*  gme_balloons.js
*  gme_vector_layers.js

Your server will also need to host a small proxy service, 'redirect.py' in this 
example, similar to the following python script:

----------
#!/usr/bin/python
import os
import urllib

content_type = "text/html"
print "Content-Type: %s\n" % content_type
fp = urllib.urlopen('http://earthbuilder.google.com/balloon?' + 
os.environ['QUERY_STRING'])
print fp.read()
fp.close()
-----------

(This CGI script could also be implemented in PHP, Perl, etc)

Original issue reported on code.google.com by avn...@google.com on 27 Aug 2012 at 10:10