2 files changed, 49 insertions, 6 deletions

diff --git a/chrome/browser/dom_ui/dom_ui_thumbnail_source.cc b/chrome/browser/dom_ui/dom_ui_thumbnail_source.cc
index 9f3d175..c3d51a1 100644
--- a/chrome/browser/dom_ui/dom_ui_thumbnail_source.cc
+++ b/chrome/browser/dom_ui/dom_ui_thumbnail_source.cc
@@ -17,27 +17,40 @@
 
 DOMUIThumbnailSource::DOMUIThumbnailSource(Profile* profile)
     : DataSource(chrome::kChromeUIThumbnailPath, MessageLoop::current()),
-      profile_(profile) {
+      profile_(profile),
+      store_(profile->GetThumbnailStore()) {
+}
+
+DOMUIThumbnailSource::~DOMUIThumbnailSource() {
+  store_->CancelPendingRequests(pending_requests_);
 }
 
 void DOMUIThumbnailSource::StartDataRequest(const std::string& path,
                                             int request_id) {
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kThumbnailStore)) {
-    ThumbnailStore* store = profile_->GetThumbnailStore();
     RefCountedBytes* data = NULL;
 
-    if (!store->GetPageThumbnail(GURL(path), &data)) {
+    ThumbnailStore::GetStatus res = store_->GetPageThumbnail(GURL(path), &data);
+    if (res == ThumbnailStore::SUCCESS) {
+      // Got the thumbnail.
+      SendResponse(request_id, data);
+    } else if (res == ThumbnailStore::FAIL) {
+      // Don't have the thumbnail so return the default thumbnail.
       if (!default_thumbnail_.get()) {
         default_thumbnail_ = new RefCountedBytes;
         ResourceBundle::GetSharedInstance().LoadImageResourceBytes(
             IDR_DEFAULT_THUMBNAIL, &default_thumbnail_->data);
       }
       SendResponse(request_id, default_thumbnail_);
-      return;
+    } else if (res == ThumbnailStore::ASYNC) {
+      // Getting the redirect list for the url. Will return thumbnail later.
+      ThumbnailStore::ThumbnailDataCallback* cb =
+          NewCallback(this, &DOMUIThumbnailSource::ReturnData);
+      pending_requests_.insert(request_id);
+      store_->GetPageThumbnailAsync(GURL(path), request_id, cb);
     }
-    SendResponse(request_id, data);
     return;
-  }
+  }  // end --thumbnail-store switch
 
   HistoryService* hs = profile_->GetHistoryService(Profile::EXPLICIT_ACCESS);
   if (hs) {
@@ -53,6 +66,22 @@ void DOMUIThumbnailSource::StartDataRequest(const std::string& path,
   }
 }
 
+void DOMUIThumbnailSource::ReturnData(int request_id,
+                                      scoped_refptr<RefCountedBytes> data) {
+  pending_requests_.erase(request_id);
+  if (data.get() && !data->data.empty()) {
+    SendResponse(request_id, data);
+  } else {
+    if (!default_thumbnail_.get()) {
+      default_thumbnail_ = new RefCountedBytes;
+      ResourceBundle::GetSharedInstance().LoadImageResourceBytes(
+          IDR_DEFAULT_THUMBNAIL, &default_thumbnail_->data);
+    }
+
+    SendResponse(request_id, default_thumbnail_);
+  }
+}
+
 void DOMUIThumbnailSource::OnThumbnailDataAvailable(
     HistoryService::Handle request_handle,
     scoped_refptr<RefCountedBytes> data) {
diff --git a/chrome/browser/dom_ui/dom_ui_thumbnail_source.h b/chrome/browser/dom_ui/dom_ui_thumbnail_source.h
index 6b9be7e..b694466 100644
--- a/chrome/browser/dom_ui/dom_ui_thumbnail_source.h
+++ b/chrome/browser/dom_ui/dom_ui_thumbnail_source.h
@@ -5,6 +5,7 @@
 #ifndef CHROME_BROWSER_DOM_UI_DOM_UI_THUMBNAIL_SOURCE_H_
 #define CHROME_BROWSER_DOM_UI_DOM_UI_THUMBNAIL_SOURCE_H_
 
+#include <set>
 #include <string>
 
 #include "base/basictypes.h"
@@ -13,17 +14,24 @@
 #include "chrome/browser/history/history.h"
 
 class Profile;
+class ThumbnailStore;
 
 // ThumbnailSource is the gateway between network-level chrome:
 // requests for thumbnails and the history backend that serves these.
 class DOMUIThumbnailSource : public ChromeURLDataManager::DataSource {
  public:
   explicit DOMUIThumbnailSource(Profile* profile);
+  virtual ~DOMUIThumbnailSource();
 
   // Called when the network layer has requested a resource underneath
   // the path we registered.
   virtual void StartDataRequest(const std::string& path, int request_id);
 
+  // Used only when chromium is invoked with the --thumbnail-store switch.
+  // If StartDataRequest does not return thumbnail data synchronously, this
+  // method will be invoked when the thumbnail data becomes available.
+  virtual void ReturnData(int request_id, scoped_refptr<RefCountedBytes> data);
+
   virtual std::string GetMimeType(const std::string&) const {
     // We need to explicitly return a mime type, otherwise if the user tries to
     // drag the image they get no extension.
@@ -38,6 +46,12 @@ class DOMUIThumbnailSource : public ChromeURLDataManager::DataSource {
   Profile* profile_;
   CancelableRequestConsumerT<int, 0> cancelable_consumer_;
 
+  // A set of outstanding request_id's. These are canceled on destruction.
+  std::set<int> pending_requests_;
+
+  // The ThumbnailStore from which thumbnails are requested.
+  scoped_refptr<ThumbnailStore> store_;
+
   // Raw PNG representation of the thumbnail to show when the thumbnail
   // database doesn't have a thumbnail for a webpage.
   scoped_refptr<RefCountedBytes> default_thumbnail_;