[WIP] Fix history.replaceState() not propagating back favicons

components/history/core/browser/history_backend.cc

Index: components/history/core/browser/history_backend.cc
diff --git a/components/history/core/browser/history_backend.cc b/components/history/core/browser/history_backend.cc
index 1c4aa6a0436526c8c33c228708c1e585b47a3127..c81501a9f2969fd8211b3963e806673df9e01f92 100644
--- a/components/history/core/browser/history_backend.cc
+++ b/components/history/core/browser/history_backend.cc
@@ -472,10 +472,19 @@ void HistoryBackend::AddPage(const HistoryAddPageArgs& request) {
   bool is_keyword_generated = ui::PageTransitionCoreTypeIs(
       request_transition, ui::PAGE_TRANSITION_KEYWORD_GENERATED);
 
+  RedirectList redirects = request.redirects;

[sky, 2017/06/22 15:26:39]

This is worth a comment.
Also, avoid the potential unnecessary copy of redirects here. By that I mean do
something like:

RedirectList redirects;
if (your-new-code) {
} else {
  redirects = request.redirects;
}

+  if (request.replaced_entry_url.has_value()) {
+    RedirectList prior_redirects;
+    GetCachedRecentRedirects(*request.replaced_entry_url, &prior_redirects);
+    prior_redirects.insert(prior_redirects.end(), redirects.begin(),
+                           redirects.end());
+    redirects = std::move(prior_redirects);
+  }
+
   // If the user is navigating to a not-previously-typed intranet hostname,
   // change the transition to TYPED so that the omnibox will learn that this is
   // a known host.
-  bool has_redirects = request.redirects.size() > 1;
+  bool has_redirects = redirects.size() > 1;
   if (ui::PageTransitionIsMainFrame(request_transition) &&
       !ui::PageTransitionCoreTypeIs(request_transition,
                                     ui::PAGE_TRANSITION_TYPED) &&
@@ -483,7 +492,7 @@ void HistoryBackend::AddPage(const HistoryAddPageArgs& request) {
     // Check both the start and end of a redirect chain, since the user will
     // consider both to have been "navigated to".
     if (IsUntypedIntranetHost(request.url) ||
-        (has_redirects && IsUntypedIntranetHost(request.redirects[0]))) {
+        (has_redirects && IsUntypedIntranetHost(redirects[0]))) {
       request_transition = ui::PageTransitionFromInt(
           ui::PAGE_TRANSITION_TYPED |
           ui::PageTransitionGetQualifier(request_transition));
@@ -515,7 +524,6 @@ void HistoryBackend::AddPage(const HistoryAddPageArgs& request) {
 
     ui::PageTransition redirect_info = ui::PAGE_TRANSITION_CHAIN_START;
 
-    RedirectList redirects = request.redirects;
     if (redirects[0].SchemeIs(url::kAboutScheme)) {
       // When the redirect source + referrer is "about" we skip it. This
       // happens when a page opens a new frame/window to about:blank and then
@@ -547,7 +555,7 @@ void HistoryBackend::AddPage(const HistoryAddPageArgs& request) {
         // can be called a lot, for example, the page cycler, and most of the
         // time we won't have changed anything.
         VisitRow visit_row;
-        if (request.did_replace_entry &&
+        if (request.replaced_entry_url.has_value() &&
             db_->GetRowForVisit(last_ids.second, &visit_row) &&
             visit_row.transition & ui::PAGE_TRANSITION_CHAIN_END) {
           visit_row.transition = ui::PageTransitionFromInt(
@@ -2086,20 +2094,8 @@ bool HistoryBackend::SetFaviconMappingsForPageAndRedirects(
   // all the pages in the redirect chain if it redirected.
   RedirectList redirects;
   GetCachedRecentRedirects(page_url, &redirects);
-  bool mappings_changed = SetFaviconMappingsForPages(redirects, icon_type,
-                                                     icon_ids);
-  if (page_url.has_ref()) {
-    // Refs often gets added by Javascript, but the redirect chain is keyed to
-    // the URL without a ref.
-    GURL::Replacements replacements;
-    replacements.ClearRef();
-    GURL page_url_without_ref = page_url.ReplaceComponents(replacements);
-    GetCachedRecentRedirects(page_url_without_ref, &redirects);
-    mappings_changed |= SetFaviconMappingsForPages(redirects, icon_type,
-                                                   icon_ids);
-  }
 
-  return mappings_changed;
+  return SetFaviconMappingsForPages(redirects, icon_type, icon_ids);
 }
 
 bool HistoryBackend::SetFaviconMappingsForPages(