[Tests not passing yet] Remove prerender sessionStorage namespace merging.

chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc

Index: chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc
diff --git a/chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc b/chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc
index 854f3a4d55e8e82ceef9d5f7db629b522b86c700..a23756dd2d63df6c802ecb7030244570ac62eebc 100644
--- a/chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc
+++ b/chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc
@@ -19,7 +19,6 @@
 #include "chrome/browser/prefetch/prefetch.h"
 #include "chrome/browser/prerender/prerender_manager.h"
 #include "chrome/browser/prerender/prerender_manager_factory.h"
-#include "chrome/browser/prerender/prerender_pending_swap_throttle.h"
 #include "chrome/browser/prerender/prerender_resource_throttle.h"
 #include "chrome/browser/prerender/prerender_tracker.h"
 #include "chrome/browser/prerender/prerender_util.h"
@@ -543,11 +542,6 @@ void ChromeResourceDispatcherHostDelegate::AppendStandardResourceThrottles(
   if (info->GetVisibilityState() == blink::WebPageVisibilityStatePrerender) {
     throttles->push_back(new prerender::PrerenderResourceThrottle(request));
   }
-  if (prerender_tracker_->IsPendingSwapRequestOnIOThread(
-          info->GetChildID(), info->GetRenderFrameID(), request->url())) {
-    throttles->push_back(new prerender::PrerenderPendingSwapThrottle(
-        request, prerender_tracker_));
-  }
 }
 
 #if defined(ENABLE_ONE_CLICK_SIGNIN)