[ios] Automatically fail any WebTest whose render process crashes.

ios/web/web_state/global_web_state_event_tracker.mm

Index: ios/web/web_state/global_web_state_event_tracker.mm
diff --git a/ios/web/web_state/global_web_state_event_tracker.mm b/ios/web/web_state/global_web_state_event_tracker.mm
index 0587e1dffb54f572116e30379b76fd20d6435d87..dba5b5fa4b110279452d3df0e390590d60e9e587 100644
--- a/ios/web/web_state/global_web_state_event_tracker.mm
+++ b/ios/web/web_state/global_web_state_event_tracker.mm
@@ -39,6 +39,7 @@ class WebStateEventForwarder : public WebStateUserData<WebStateEventForwarder>,
   void DidStartLoading() override;
   void DidStopLoading() override;
   void PageLoaded(PageLoadCompletionStatus load_completion_status) override;
+  void RenderProcessGone() override;
   void WebStateDestroyed() override;
 
   DISALLOW_COPY_AND_ASSIGN(WebStateEventForwarder);
@@ -82,6 +83,10 @@ void WebStateEventForwarder::PageLoaded(
                                                         load_completion_status);
 }
 
+void WebStateEventForwarder::RenderProcessGone() {
+  GlobalWebStateEventTracker::GetInstance()->RenderProcessGone(web_state());
+}
+
 void WebStateEventForwarder::WebStateDestroyed() {
   GlobalWebStateEventTracker::GetInstance()->WebStateDestroyed(web_state());
 }
@@ -145,6 +150,11 @@ void GlobalWebStateEventTracker::PageLoaded(
     observer.PageLoaded(web_state, load_completion_status);
 }
 
+void GlobalWebStateEventTracker::RenderProcessGone(WebState* web_state) {
+  for (auto& observer : observer_list_)
+    observer.RenderProcessGone(web_state);
+}
+
 void GlobalWebStateEventTracker::WebStateDestroyed(WebState* web_state) {
   for (auto& observer : observer_list_)
     observer.WebStateDestroyed(web_state);