[Sync] Speed up sync node browser/search in about:sync

chrome/browser/sync/syncable/syncable.h

Index: chrome/browser/sync/syncable/syncable.h
diff --git a/chrome/browser/sync/syncable/syncable.h b/chrome/browser/sync/syncable/syncable.h
index cace53e327a93e1d251231a2d5de470f94ce88ac..f6d51de0fc7197102445d15357ccade701b6001c 100644
--- a/chrome/browser/sync/syncable/syncable.h
+++ b/chrome/browser/sync/syncable/syncable.h
@@ -847,7 +847,11 @@ class Directory {
   typedef std::vector<int64> ChildHandles;
 
   // Returns the child meta handles for given parent id.
-  void GetChildHandles(BaseTransaction*, const Id& parent_id,
+  void GetChildHandlesById(BaseTransaction*, const Id& parent_id,
+      ChildHandles* result);
+
+  // Returns the child meta handles for given meta handle.
+  void GetChildHandlesByHandle(BaseTransaction*, int64 handle,
       ChildHandles* result);
 
   // Find the first or last child in the positional ordering under a parent,
@@ -873,6 +877,9 @@ class Directory {
   // WARNING: THIS METHOD PERFORMS SYNCHRONOUS I/O VIA SQLITE.
   bool SaveChanges();
 
+  // Fill in |result| with all meta handles.
+  void GetAllMetaHandles(BaseTransaction* trans, MetahandleSet* result);
+
   // Returns the number of entities with the unsynced bit set.
   int64 unsynced_entity_count() const;
 
@@ -942,7 +949,6 @@ class Directory {
   void InsertEntry(EntryKernel* entry);
 
   // Used by CheckTreeInvariants
-  void GetAllMetaHandles(BaseTransaction* trans, MetahandleSet* result);
   bool SafeToPurgeFromMemory(const EntryKernel* const entry) const;
 
   // Internal setters that do not acquire a lock internally.  These are unsafe
@@ -1072,6 +1078,11 @@ class Directory {
       const ScopedKernelLock& lock,
       const Id& parent_id);
 
+  // Fill in |result| with the handles of the children of |parent_id|.
+  void GetChildHandles(
+      const ScopedKernelLock& lock,
+      const Id& parent_id, Directory::ChildHandles* result);
+
   Kernel* kernel_;
 
   DirectoryBackingStore* store_;