Remove fixed chromebot crash signatures.

chrome/test/data/reliability/known_crashes.txt

Index: chrome/test/data/reliability/known_crashes.txt
diff --git a/chrome/test/data/reliability/known_crashes.txt b/chrome/test/data/reliability/known_crashes.txt
index 65efb73d399354abf3b5baabffddacb55df12e44..79111f92e9d18e97e278add9e2f287f72b1f3378 100644
--- a/chrome/test/data/reliability/known_crashes.txt
+++ b/chrome/test/data/reliability/known_crashes.txt
@@ -49,11 +49,6 @@ PREFIX : messageloop::runtask___messageloop::deferorrunpendingtask___messageloop
 # 48712
 PREFIX : npapi::plugininstance::npp_newstream
 
-# 49254
-SUBSTRING : std::_tree<std::_tmap_traits<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,net::internal::clientsocketpoolbasehelper::group,std::less<std::basic_string<char,std::char_traits<char>,std::allocator<char> > >,std::allocator<std::pair<std::basic_string<char,std::char_traits<char>,std::allocator<char> > const ,net::internal::clientsocketpoolbasehelper::group> >,0> >::erase___net::internal::clientsocketpoolbasehelper::onavailablesocketslot
-SUBSTRING : std::_tree<std::_tmap_traits<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,net::internal::clientsocketpoolbasehelper::group,std::less<std::basic_string<char,std::char_traits<char>,std::allocator<char> > >,std::allocator<std::pair<std::basic_string<char,std::char_traits<char>,std::allocator<char> > const ,net::internal::clientsocketpoolbasehelper::group> >,0> >::_lbound___std::_tree<std::_tmap_traits<std::basic_string<char,std::char_traits<char>,std::allocator<char> >,net::internal::clientsocketpoolbasehelper::group,std::less<std::basic_string<char,std::char_traits<char>,std::allocator<char> > >,std::allocator<std::pair<std::basic_string<char,std::char_traits<char>,std::allocator<char> > const ,net::internal::clientsocketpoolbasehelper::group> >,0> >::find___net::internal::clientsocketpoolbasehelper::onavailablesocketslot
-
-
 # 49271
 PREFIX : messageloop::posttask_helper___messageloop::posttask___disk_cache::inflightio::oniocomplete___disk_cache::backendio::executebackendoperation___messageloop::runtask___messageloop::dowork___base::messagepumpforio::dorunloop___base::messagepumpwin::run___messageloop::runinternal___messageloop::run___base::thread::run___base::thread::threadmain___`anonymous namespace'::threadfunc