Prioritize smaller favicons over larger ones for tabs, etc.

chrome/browser/favicon/favicon_handler.cc

Index: chrome/browser/favicon/favicon_handler.cc
diff --git a/chrome/browser/favicon/favicon_handler.cc b/chrome/browser/favicon/favicon_handler.cc
index cc19d92541f23d57081a84c2bf2027bfbd7343d1..f6f3e54d1aa432328462781724902248b6862889 100644
--- a/chrome/browser/favicon/favicon_handler.cc
+++ b/chrome/browser/favicon/favicon_handler.cc
@@ -51,6 +51,8 @@ bool DoUrlAndIconMatch(const FaviconURL& favicon_url,
 
 }  // namespace
 
+////////////////////////////////////////////////////////////////////////////////
+
 FaviconHandler::DownloadRequest::DownloadRequest()
     : icon_type(history::INVALID_ICON) {
 }
@@ -69,6 +71,28 @@ FaviconHandler::DownloadRequest::DownloadRequest(
       icon_type(icon_type) {
 }
 
+////////////////////////////////////////////////////////////////////////////////
+
+FaviconHandler::FaviconCandidate::FaviconCandidate()
+    : icon_type(history::INVALID_ICON) {
+}
+
+FaviconHandler::FaviconCandidate::~FaviconCandidate() {
+}
+
+FaviconHandler::FaviconCandidate::FaviconCandidate(
+    const GURL& url,
+    const GURL& image_url,
+    const gfx::Image& image,
+    history::IconType icon_type)
+    : url(url),
+      image_url(image_url),
+      image(image),
+      icon_type(icon_type) {
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
 FaviconHandler::FaviconHandler(Profile* profile,
                                FaviconHandlerDelegate* delegate,
                                Type icon_type)
@@ -101,6 +125,7 @@ void FaviconHandler::FetchFavicon(const GURL& url) {
   favicon_expired_ = got_favicon_from_history_ = false;
   current_url_index_ = 0;
   urls_.clear();
+  favicon_candidates_.clear();
 
   // Request the favicon from the history service. In parallel to this the
   // renderer is going to notify us (well TabContents) when the favicon url is
@@ -124,12 +149,42 @@ FaviconService* FaviconHandler::GetFaviconService() {
   return profile_->GetFaviconService(Profile::EXPLICIT_ACCESS);
 }
 
+void FaviconHandler::SetFaviconFromCandidates() {
+  if (favicon_candidates_.empty())
+    return;
+  const int preferred_size = preferred_icon_size();
+  FaviconCandidates::iterator match;
+  if (preferred_size == 0) {
+    // No size preference, use the first icon.
+    match = favicon_candidates_.begin();
+  } else {
+    // Use the icon closest to preferred_size, favoring sizes >= preferred_size.
+    int match_size = -1;
+    for (FaviconCandidates::iterator iter = favicon_candidates_.begin();
+         iter != favicon_candidates_.end(); ++iter) {
+      FaviconCandidate& candidate = *iter;
+      SkBitmap bitmap = *candidate.image.ToSkBitmap();
+      int bitmap_size = std::max(bitmap.width(), bitmap.height());
+      if (match_size < 0 ||
+          (bitmap_size >= preferred_size && bitmap_size < match_size) ||
+          (match_size < preferred_size && bitmap_size > match_size)) {
+        match = iter;
+        match_size = bitmap_size;
+        if (bitmap_size == preferred_size)
+          break;
+      }
+    }
+  }
+  SetFavicon(match->url, match->image_url, match->image, match->icon_type);
+  favicon_candidates_.clear();
+}
+
 void FaviconHandler::SetFavicon(
     const GURL& url,
     const GURL& image_url,
     const gfx::Image& image,
     history::IconType icon_type) {
-  const SkBitmap& bitmap = image;
+  SkBitmap bitmap = *image.ToSkBitmap();
   const gfx::Image& sized_image = (preferred_icon_size() == 0 ||
       (preferred_icon_size() == bitmap.width() &&
        preferred_icon_size() == bitmap.height())) ?
@@ -143,8 +198,10 @@ void FaviconHandler::SetFavicon(
 
   if (url == url_ && icon_type == history::FAVICON) {
     NavigationEntry* entry = GetEntry();
-    if (entry)
+    if (entry) {
+      entry->GetFavicon().url = image_url;
       UpdateFavicon(entry, &sized_image);
+    }
   }
 }
 
@@ -236,12 +293,18 @@ void FaviconHandler::OnDidDownloadFavicon(int id,
     // The downloaded icon is still valid when there is no FaviconURL update
     // during the downloading.
     if (!errored) {
-      SetFavicon(i->second.url, image_url, image, i->second.icon_type);
-    } else if (GetEntry() && ++current_url_index_ < urls_.size()) {
-      // Copies all candidate except first one and notifies the FaviconHandler,
+      favicon_candidates_.push_back(FaviconCandidate(
+          i->second.url, image_url, image, i->second.icon_type));

[michaelbai, 2012/03/14 22:34:14]

Would you like stop fetch the rest of icons if the preferred_size == 
bitmap_size?

It will reduce the network access, and the right favicon could be stored before
the next page loaded.

[stevenjb, 2012/03/15 00:45:53]

Yes that would be better. I thought of this but didn't want to convert from
gfx::Image yet again. I think what I really need to do is cache the SkBitmap in
the Candidate.

Done.

[michaelbai, 2012/03/15 01:12:00]

It seemed you don't need favicon_candidates_ vector, just store the currently
best matched one while you downloading the icon

On 2012/03/15 00:45:53, stevenjb (chromium) wrote:

[stevenjb, 2012/03/15 21:05:10]

That's a fair point. I did another round of re-factoring.

+    }
+    if ((errored || preferred_icon_size() != 0) &&
+        (GetEntry() && ++current_url_index_ < urls_.size())) {
+      // Copies all candidates except the first and notifies the FaviconHandler,
       // so the next candidate can be processed.
       std::vector<FaviconURL> new_candidates(urls_.begin() + 1, urls_.end());
       OnUpdateFaviconURL(0, new_candidates);
+    } else {
+      // We have all candidates, choose one and set the favicon.
+      SetFaviconFromCandidates();
     }
   }
   download_requests_.erase(i);