Cancel prerenders that spawn post requests.

content/browser/renderer_host/resource_dispatcher_host.cc

Index: content/browser/renderer_host/resource_dispatcher_host.cc
diff --git a/content/browser/renderer_host/resource_dispatcher_host.cc b/content/browser/renderer_host/resource_dispatcher_host.cc
index c32d8b907695b8f02805d9dcebd470ebdca10201..9535cee2d01ad87cdf704260c911ecef6da41621 100644
--- a/content/browser/renderer_host/resource_dispatcher_host.cc
+++ b/content/browser/renderer_host/resource_dispatcher_host.cc
@@ -423,6 +423,19 @@ void ResourceDispatcherHost::BeginRequest(
     // Otherwise, treat like a normal request, and fall-through.
   }
 
+  // Abort any prerenders that spawn requests that use invalid HTTP methods.
+  if (is_prerendering &&
+      !prerender::PrerenderManager::IsValidHttpMethod(request_data.method)) {
+    BrowserThread::PostTask(
+        BrowserThread::UI, FROM_HERE,
+        NewRunnableFunction(
+            prerender::DestroyPreloadForChildRouteIdPairOnUIThread,
+            resource_context.prerender_manager(),
+            std::make_pair(child_id, route_id),
+            prerender::FINAL_STATUS_INVALID_HTTP_METHOD));
+    AbortRequestBeforeItStarts(filter_, sync_result, route_id, request_id);
+    return;
+  }
 
   // Construct the event handler.
   scoped_refptr<ResourceHandler> handler;