When I specified the rlz chrome extension api, I explicitly did not include a...

When I specified the rlz chrome extension api, I explicitly did not include a
function to send pings to google for two reasons:

- I thought that chrome's own rlz pings would send all rlz information for all
  other products installed on the machine
- I did not want to allow an extension to DoS google by sending too many rlz
  pings

It turns out that the rlz library itself makes sure that a given product's
pings are never sent out more than once per day, as is required for rlz, so
there is no DoS danger by exposing a ping function.  Also, I was wrong in 
thinking that chrome's rlz pings would send out all rlz information about
other products installed on the machine: it sends out the other products rlz
strings, but it does not send out the other products rlz event information.
This makes sense since there are signatures and brand codes and other
information that cannot be determined by chrome for the extensions.

So adding a new rlz chrome extension function to expose sending pings.

BUG=None
TEST=See particular extension using this api


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=52800

[Aaron Boodman, 2010-07-15 18:38:44]

lgtm

[Roger Tawa OOO till Jul 10th, 2010-07-16 18:30:40]

Hi Aaron,

The failure of the win try bot made me realize that I forgot to include one file
in the CL: extension_function_dispatcher.cc.  The other files are unchanged. 
Could you take another look please?  Thanks,

[Aaron Boodman, 2010-07-16 19:31:54]

still lgtm