gdata: Add GDataCache::GetResourceIdsOfAllFiles()

chrome/browser/chromeos/gdata/gdata_cache.h

Index: chrome/browser/chromeos/gdata/gdata_cache.h
diff --git a/chrome/browser/chromeos/gdata/gdata_cache.h b/chrome/browser/chromeos/gdata/gdata_cache.h
index 1c1f0adfcd8b934902f5b0d672e6eea6e6c5142e..5aa8a06cb2faf4902a24425d1e43273a3d7d307c 100644
--- a/chrome/browser/chromeos/gdata/gdata_cache.h
+++ b/chrome/browser/chromeos/gdata/gdata_cache.h
@@ -168,12 +168,19 @@ class GDataCache {
   void GetResourceIdsOfBacklogOnUIThread(
       const GetResourceIdsOfBacklogCallback& callback);
 
-  // Gets the resource IDs of all pinned files, including pinned dirty files.
+  // Gets the resource IDs of all exsiting (i.e. cached locally) pinned
+  // files, including pinned dirty files.
   //
   // Must be called on UI thread. |callback| is run on UI thread.
   void GetResourceIdsOfExistingPinnedFilesOnUIThread(
       const GetResourceIdsCallback& callback);
 
+  // Gets the resource IDs of all files in the cache.
+  //
+  // Must be called on UI thread. |callback| is run on UI thread.
+  void GetResourceIdsOfAllFilesOnUIThread(
+      const GetResourceIdsCallback& callback);
+
   // Frees up disk space to store the given number of bytes, while keeping
   // kMinFreSpace bytes on the disk, if needed.  |has_enough_space| is
   // updated to indicate if we have enough space.
@@ -331,6 +338,10 @@ class GDataCache {
   void GetResourceIdsOfExistingPinnedFiles(
       std::vector<std::string>* resource_ids);
 
+  // Used to implement GetResourceIdsOfAllFilesOnUIThread.
+  void GetResourceIdsOfAllFiles(
+      std::vector<std::string>* resource_ids);
+
   // Used to implement GetFileOnUIThread.
   void GetFile(const std::string& resource_id,
                const std::string& md5,