BFCache: Make navigation/back-to-get-after-post work with BFCache

On backward/forward navigations, backward/forward cache changes some
behavior around the navigation.

This CL updates a test navigation/back-to-get-after-post to work
with backward/forward cache.


Bug: 1132180
Change-Id: I86a99eddffbe8c25dc932258035214a60314b34b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2520557Reviewed-by: Fergal Daly <fergal@chromium.org>
Reviewed-by: Rakina Zata Amni <rakina@chromium.org>
Commit-Queue: Hitoshi Yoshida <peria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826157}

third_party/blink/web_tests/http/tests/navigation/back-to-get-after-post.php

@@ -13,7 +13,7 @@ if (window.testRunner) {
     testRunner.waitUntilDone();
 }
 
-window.onload = function() {
+window.onpageshow = function() {
     setTimeout(function() {
         if (sessionStorage.getItem("backToGet") == null) {
             sessionStorage.setItem("backToGet", "step1");

third_party/blink/web_tests/http/tests/navigation/resources/back-to-get-after-post-helper.html

 <script>
-window.onload = function() {
+window.onpageshow = function() {
     setTimeout(function() {
         if (sessionStorage.getItem("backToGet") == "step1") {
             sessionStorage.setItem("backToGet", "step2");