Add TopSites::GetTemporaryThumbnailScore().

chrome/browser/history/top_sites.cc

Index: chrome/browser/history/top_sites.cc
diff --git a/chrome/browser/history/top_sites.cc b/chrome/browser/history/top_sites.cc
index 71d3316cbb1bfe15adc2b82dad942d7e1fd858e7..2d38aec9cb70246119483b253a67ade92772f047 100644
--- a/chrome/browser/history/top_sites.cc
+++ b/chrome/browser/history/top_sites.cc
@@ -247,6 +247,15 @@ bool TopSites::GetPageThumbnail(const GURL& url,
                                 scoped_refptr<RefCountedBytes>* bytes) {
   // WARNING: this may be invoked on any thread.
   base::AutoLock lock(lock_);

[sky, 2011/04/11 14:31:09]

The rest of the class doesn't lock around lock_ when using temp_images_, so
using lock_ doesn't make the code any more thread safe.

Instead of trying to change this method to do two things, add a method that
returns if we have a temp thumbnail. The new method won't need any locks as it's
only for use on the UI thread.

[satorux1, 2011/04/11 15:19:09]

That makes a lot of sense. I've updated the patch and added a new method
GetTemporaryPageThumbnailScore(), and changed ThumbnailGenerator to use it.

Please take another look.

+
+  // The thumbnail may be found in the temporary images.
+  for (TempImages::iterator i = temp_images_.begin(); i != temp_images_.end();
+       ++i) {
+    if (i->first == url) {
+      *bytes = i->second.thumbnail;
+      return true;
+    }
+  }
   return thread_safe_cache_->GetPageThumbnail(url, bytes);
 }
 
@@ -254,6 +263,15 @@ bool TopSites::GetPageThumbnailScore(const GURL& url,
                                      ThumbnailScore* score) {
   // WARNING: this may be invoked on any thread.
   base::AutoLock lock(lock_);
+
+  // The thumbnail score may be found in the temporary images.
+  for (TempImages::iterator i = temp_images_.begin(); i != temp_images_.end();
+       ++i) {
+    if (i->first == url) {
+      *score = i->second.thumbnail_score;
+      return true;
+    }
+  }
   return thread_safe_cache_->GetPageThumbnailScore(url, score);
 }