Refactoring of job dispatch in HostResolverImpl in preparation for DnsClient.

net/net.gyp

Index: net/net.gyp
diff --git a/net/net.gyp b/net/net.gyp
index acbbe6c343e118a5c20940c1bc7254dfc93145ed..385bb7ede619eefaefa7f5f98db9a877fa108481 100644
--- a/net/net.gyp
+++ b/net/net.gyp
@@ -200,6 +200,9 @@
         'base/platform_mime_util_linux.cc',
         'base/platform_mime_util_mac.cc',
         'base/platform_mime_util_win.cc',
+        'base/priority_dispatch.cc',
+        'base/priority_dispatch.h',
+        'base/priority_queue.h',
         'base/rand_callback.h',
         'base/registry_controlled_domain.cc',
         'base/registry_controlled_domain.h',
@@ -1032,6 +1035,8 @@
         'base/network_change_notifier_win_unittest.cc',
         'base/origin_bound_cert_service_unittest.cc',
         'base/pem_tokenizer_unittest.cc',
+        'base/priority_dispatch_unittest.cc',
+        'base/priority_queue_unittest.cc',
         'base/registry_controlled_domain_unittest.cc',
         'base/run_all_unittests.cc',
         'base/sdch_filter_unittest.cc',