Add pending preloads indexed by routing id. Start preloading once we navigate.

chrome/browser/prerender/prerender_manager.cc

Index: chrome/browser/prerender/prerender_manager.cc
diff --git a/chrome/browser/prerender/prerender_manager.cc b/chrome/browser/prerender/prerender_manager.cc
index f857c70a64fc0eb6bddb6822d2d883bf76eb7d0c..30edf7dc55ca51af91c868022c45b667e0abc3a3 100644
--- a/chrome/browser/prerender/prerender_manager.cc
+++ b/chrome/browser/prerender/prerender_manager.cc
@@ -107,6 +107,17 @@ bool PrerenderManager::AddPreload(const GURL& url,
   return true;
 }
 
+void PrerenderManager::AddPendingPreload(int route_id,
+                                         const GURL& url,
+                                         const std::vector<GURL>& alias_urls,
+                                         const GURL& referrer) {
+  DCHECK(pending_prerender_map_.find(route_id) == pending_prerender_map_.end());

[cbentzel, 2011/03/14 14:32:26]

What if there are two <link rel="prefetch"> elements on the page that is
prerendered? This will trigger then.

[dominich, 2011/03/14 17:47:15]

Good catch. I can remove the DCHECK, but perhaps it is better to also change the
container from a map to something like a vector of pairs. Then on navigation I
can trigger all of the prerenders for the page in the right order and let the
existing logic take care of which start. What do you think?

+
+  pending_prerender_map_.insert(
+        std::make_pair<int, PendingContentsData>(route_id,
+                              PendingContentsData(url, alias_urls, referrer)));
+}
+
 void PrerenderManager::DeleteOldEntries() {
   while (!prerender_list_.empty()) {
     PrerenderContentsData data = prerender_list_.front();
@@ -155,6 +166,16 @@ bool PrerenderManager::MaybeUsePreloadedPage(TabContents* tc, const GURL& url) {
   tc->SwapInRenderViewHost(rvh);
   tc->set_was_prerendered(true);
 
+  // See if we have any pending prerender requests for this routing id and start
+  // the preload if we do.
+  std::map<int, PendingContentsData>::iterator pending_it =
+      pending_prerender_map_.find(rvh->routing_id());
+  if (pending_it != pending_prerender_map_.end()) {
+    const PendingContentsData& data = pending_it->second;
+    AddPreload(data.url_, data.alias_urls_, data.referrer_);
+    pending_prerender_map_.erase(pending_it);
+  }
+
   ViewHostMsg_FrameNavigate_Params* p = pc->navigate_params();
   if (p != NULL)
     tc->DidNavigate(rvh, *p);
@@ -179,6 +200,7 @@ void PrerenderManager::RemoveEntry(PrerenderContents* entry) {
        it != prerender_list_.end();
        ++it) {
     if (it->contents_ == entry) {
+      RemovePendingPreload(entry);
       prerender_list_.erase(it);
       break;
     }
@@ -267,6 +289,21 @@ void PrerenderManager::RecordPrefetchTagObservedOnUIThread() {
   last_prefetch_seen_time_ = base::TimeTicks::Now();
 }
 
+void PrerenderManager::RemovePendingPreload(PrerenderContents* entry) {
+  RenderViewHost* rvh = entry->render_view_host();
+
+  // If the entry doesn't have a RenderViewHost then it didn't start
+  // prerendering and there shouldn't be any pending preloads to remove.
+  if (rvh == NULL)
+    return;
+
+  int route_id = rvh->routing_id();
+  std::map<int, PendingContentsData>::iterator it =
+      pending_prerender_map_.find(route_id);
+  if (it != pending_prerender_map_.end())
+    pending_prerender_map_.erase(it);
+}
+
 // static
 bool PrerenderManager::ShouldRecordWindowedPPLT() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));