[chromedriver] Add Network Conditions Override Manager and tests

chrome/test/chromedriver/session.h

Index: chrome/test/chromedriver/session.h
diff --git a/chrome/test/chromedriver/session.h b/chrome/test/chromedriver/session.h
index 2df16d7ae6912c4ae08824f94ada9edd25cb9885..fa0a82d88a35d9a0313cf7ae3cc1734206878aeb 100644
--- a/chrome/test/chromedriver/session.h
+++ b/chrome/test/chromedriver/session.h
@@ -16,6 +16,7 @@
 #include "chrome/test/chromedriver/basic_types.h"
 #include "chrome/test/chromedriver/chrome/device_metrics.h"
 #include "chrome/test/chromedriver/chrome/geoposition.h"
+#include "chrome/test/chromedriver/chrome/network_conditions.h"
 #include "chrome/test/chromedriver/command_listener.h"
 
 namespace base {
@@ -72,6 +73,7 @@ struct Session {
   scoped_ptr<std::string> prompt_text;
   scoped_ptr<Geoposition> overridden_geoposition;
   scoped_ptr<DeviceMetrics> overridden_device_metrics;
+  scoped_ptr<NetworkConditions> overridden_network_conditions;
   // Logs that populate from DevTools events.
   ScopedVector<WebDriverLog> devtools_logs;
   scoped_ptr<WebDriverLog> driver_log;