[Reland] Set initiatorType to "early-hints" for Early Hints preloaded resources

The original CL was reverted due to the failure on linux-trusty-rel bot.
`ResourceResponse::WasCached()` sometimes returned false. This seems
to happen when the final response is sent immediately after a 103
response.

The diff from the original CL is to move sleep timing in the test.
Previously it slept after the final response header. In the current CL
the test sleeps before sending the final response header.

Original description:

This CL sets initiatorType of PerformanceResourceTiming to "early-hints"
when the resource is preloaded via a 103 Early Hints response. See [1]
for the motivation.

Early Hints preloads are handled in the browser process before the
navigation commit. This means that information related to Early Hints
preloads need to be plumbed from the browser to the page's renderer
process so that the ResourceFetcher in the renderer process can set
initatorType to "early-hints". The propagation works as follows:

[browser process]
(navigation commit)
=> NavigationRequest gets information related to preloads from
   NavigaitonEarlyHintsManager
=> These information are set to mojom::CommitNavigationParams

[renderer process]
(RenderFrameImpl receives mojom::CommitNavigationParams)
=> RenderFrameImpl converts mojom::CommitNavigationParams to
   WebNavigationParams then passes it to DocumentLoader
=> FrameFetchContext creates a ResourceFetcher from DocumentLoader and
   passes information related to Early Hints preloads to the fetcher
   via DocumentLoader

When the ResourceFetcher fetches a resource it looks up Early Hints
preloads. If there is matching URL, it sets initiatorType to
"early-hints".

[1] https://github.com/w3c/resource-timing/issues/273#issuecomment-845716308

Bug: 1212542, 1221106
Change-Id: Ie9194d458f065fbc49369f462cee0d906076fbcf
Cq-Include-Trybots: luci.chromium.try:linux-trusty-rel
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2971665
Reviewed-by: Kinuko Yasuda <[email protected]>
Commit-Queue: Kenichi Ishibashi <[email protected]>
Cr-Commit-Position: refs/heads/master@{#894139}
diff --git a/content/browser/renderer_host/navigation_controller_impl.cc b/content/browser/renderer_host/navigation_controller_impl.cc
index fb118bd..6f796d39 100644
--- a/content/browser/renderer_host/navigation_controller_impl.cc
+++ b/content/browser/renderer_host/navigation_controller_impl.cc
@@ -3528,7 +3528,8 @@
           std::vector<
               mojom::AppHistoryEntryPtr>() /* app_history_back_entries */,
           std::vector<
-              mojom::AppHistoryEntryPtr>() /* app_history_forward_entries */);
+              mojom::AppHistoryEntryPtr>() /* app_history_forward_entries */,
+          std::vector<GURL>() /* early_hints_preloaded_resources */);
 #if defined(OS_ANDROID)
   if (ValidateDataURLAsString(params.data_url_as_string)) {
     commit_params->data_url_as_string = params.data_url_as_string->data();