Fix leak in PrerenderResourceHandlerTest.

Fix leak in PrerenderResouceHandlerTest.

ResourceHandler's expect to be deleted on the IO thread after their ref count goes to 0. Change the unit test to explicitly drop ref count and run the IO thread's message loop. 

BUG=69414
TEST=valgrind trybots

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=71798

[cbentzel, 2011-01-14 18:58:56]

On 2011/01/14 18:57:49, cbentzel wrote:

It seems a little wrong to share the same message loop [and system thread] for
both the IO and UI thread, but I saw this in a few other tests as well.

I started down the route of having an explicit IO thread and this solution is
much much simpler.

[cbentzel, 2011-01-18 11:56:29]

The valgrind trybot failures are not PrerenderResourceHandler related.

[cbentzel, 2011-01-18 12:59:35]

On 2011/01/18 11:56:29, cbentzel wrote:
> The valgrind trybot failures are not PrerenderResourceHandler related.

And, the most recent bot failures are due to problems updating suppressions.txt.
Not sure why that patch isn't working.

Anyway, this is fine to review.

[gavinp, 2011-01-18 22:25:05]

LGTM!

http://codereview.chromium.org/6136006/diff/10001/chrome/browser/prerender/pr...
File chrome/browser/prerender/prerender_resource_handler_unittest.cc (right):

http://codereview.chromium.org/6136006/diff/10001/chrome/browser/prerender/pr...
chrome/browser/prerender/prerender_resource_handler_unittest.cc:105: //
reference count go to 0.
The grammar above confused me, especially the apostrophe.  I think a more clear
comment is:

"The ResourceHandlers will post a task to get deleted when their reference count
goes to 0."

[tburkard, 2011-01-18 23:54:10]

LGTM

[cbentzel, 2011-01-19 13:55:17]

I'll land after trybots are happy.

http://codereview.chromium.org/6136006/diff/10001/chrome/browser/prerender/pr...
File chrome/browser/prerender/prerender_resource_handler_unittest.cc (right):

http://codereview.chromium.org/6136006/diff/10001/chrome/browser/prerender/pr...
chrome/browser/prerender/prerender_resource_handler_unittest.cc:105: //
reference count go to 0.
On 2011/01/18 22:25:06, gavinp wrote:
> The grammar above confused me, especially the apostrophe.  I think a more
clear
> comment is:
> 
> "The ResourceHandlers will post a task to get deleted when their reference
count
> goes to 0."

I changed the comment to be clearer.