Media Galleries API Picasa: Make PicasaDataProvider handle async PMP and INI parsing robustly.

chrome/browser/media_galleries/fileapi/safe_picasa_albums_indexer.h

Index: chrome/browser/media_galleries/fileapi/safe_picasa_albums_indexer.h
diff --git a/chrome/browser/media_galleries/fileapi/safe_picasa_albums_indexer.h b/chrome/browser/media_galleries/fileapi/safe_picasa_albums_indexer.h
index 983652ce2921e6a3dbb300b46c5940302e209ca0..0611528852903bdab0871213520e2c0b77bdb3da 100644
--- a/chrome/browser/media_galleries/fileapi/safe_picasa_albums_indexer.h
+++ b/chrome/browser/media_galleries/fileapi/safe_picasa_albums_indexer.h
@@ -10,6 +10,7 @@
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/common/media_galleries/picasa_types.h"
 #include "content/public/browser/utility_process_host_client.h"
@@ -24,6 +25,8 @@ class Message;
 
 namespace picasa {
 
+extern const char kPicasaINIFilename[];
+
 // SafePicasaAlbumsIndexer indexes the contents of Picasa Albums by parsing the
 // INI files found in Folders. The SafePicasaAlbumsIndexer object is ref-counted
 // and kept alive after Start() is called until the ParserCallback is called.
@@ -31,8 +34,13 @@ namespace picasa {
 // utility process replies or when it dies.
 class SafePicasaAlbumsIndexer : public content::UtilityProcessHostClient {
  public:
-  typedef base::Callback<void(bool /* success */,
-                              const picasa::AlbumImagesMap&)> DoneCallback;
+  // PicasaDataProvider keeps a reference to the last-dispatched instance of
+  // this class so it can ignore callbacks from 'stale' instances. The callback
+  // also keeps a reference so it doesn't get destroyed prematurely.
+  typedef base::Callback<void(scoped_refptr<SafePicasaAlbumsIndexer>,
+                              bool parse_success,
+                              const picasa::AlbumImagesMap&)>
+      DoneCallback;
 
   SafePicasaAlbumsIndexer(const AlbumMap& albums,
                           const AlbumMap& folders,