ThemeDisplay object in portlet.js needs ability to generate virtual URLs

Per Ray Auge:

"basically 99.99% of calls through the portal come through the FriendlyURLServlet
which does the url parsing and can identify the virtual layout case
all generated urls are safe
because they will result in properly formed urls
however, the portlet.js is self generating the url
which means it will not pass through the FriendlyURLServlet
thus won't resolve the virtual layout scenario
.. before it gets to SPA
there are very few cases like this.. but they exist and have to be treated manually
however, there is no way in js to identify the virtual url case
SO
we have to provide a means to detect it
which is why I'm temporarily adding a method in the themeDisplay js object to recognize it
and then we can use that mechanism to know in the portlet.js how to create that part of the url
which is simply to provide an appropriate value for p_v_l_s_g_id "