[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 7ef302aca2e7d3b4b884097c154bf361e4abfebf..b071096c8c60580adbc7aea8e78f5cd6605d9f2a 100644
--- a/components/history/core/browser/history_backend.cc
+++ b/components/history/core/browser/history_backend.cc
@@ -83,6 +83,19 @@ void RunUnlessCanceled(
     closure.Run();
 }
 
+void ConcatMoveRedirectList(RedirectList* source, RedirectList* output) {
+  if (source->empty())
+    return;
+
+  if (output->empty()) {
+    *output = std::move(*source);
+  } else {
+    output->reserve(output->size() + source->size());
+    for (GURL& redirect : *source)
+      output->push_back(std::move(redirect));
+  }
+}
+
 }  // namespace
 
 // How long we'll wait to do a commit, so that things are batched together.
@@ -491,6 +504,7 @@ void HistoryBackend::AddPage(const HistoryAddPageArgs& request) {
   }
 
   RedirectList extended_redirect_chain;
+  RedirectList redirects = request.redirects;
 
   if (!has_redirects) {
     // The single entry is both a chain start and end.
@@ -516,8 +530,6 @@ void HistoryBackend::AddPage(const HistoryAddPageArgs& request) {
     // Redirect case. Add the redirect chain.
 
     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
@@ -549,7 +561,7 @@ 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(
@@ -590,21 +602,24 @@ void HistoryBackend::AddPage(const HistoryAddPageArgs& request) {
       // redirects.
       redirect_info = ui::PAGE_TRANSITION_SERVER_REDIRECT;
     }
+  }
 
-    // Last, save this redirect chain for later so we can set titles & favicons
-    // on the redirected pages properly. For this we use the extended redirect
-    // chain, which includes URLs from concatenated redirects.
-    if (extended_redirect_chain.empty()) {
-      extended_redirect_chain = std::move(redirects);
-    } else {
-      extended_redirect_chain.reserve(extended_redirect_chain.size() +
-                                      redirects.size());
-      for (GURL& redirect : redirects)
-        extended_redirect_chain.push_back(std::move(redirect));
-    }
-    recent_redirects_.Put(request.url, extended_redirect_chain);
+  // If the page replaced another one in history, we treat is similarly as a
+  // redirect and propagate favicon and titles through.
+  if (request.replaced_entry_url.has_value()) {
+    RedirectList replaced_url_redirects;
+    GetCachedRecentRedirects(*request.replaced_entry_url,
+                             &replaced_url_redirects);
+    ConcatMoveRedirectList(&replaced_url_redirects, &extended_redirect_chain);
   }
 
+  // Last, save this redirect chain for later so we can set titles & favicons
+  // on the redirected pages properly.
+  ConcatMoveRedirectList(&redirects, &extended_redirect_chain);
+
+  if (extended_redirect_chain.size() > 1)
+    recent_redirects_.Put(request.url, extended_redirect_chain);
+
   // TODO(brettw) bug 1140015: Add an "add page" notification so the history
   // views can keep in sync.