Add GetStoreSize() to ImageStore to know the actual db size.

components/enhanced_bookmarks/persistent_image_store.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/enhanced_bookmarks/persistent_image_store.h"
 
+#include "base/files/file.h"
 #include "components/enhanced_bookmarks/image_store_util.h"
 #include "sql/statement.h"
 #include "sql/transaction.h"
 #include "ui/gfx/geometry/size.h"
 #include "url/gurl.h"
 
 namespace {
 
 bool InitTables(sql::Connection& db) {
   const char kTableSql[] =
@@ skipping 173 matching lines @@
 void PersistentImageStore::ClearAll() {
   DCHECK(sequence_checker_.CalledOnValidSequencedThread());
   if (OpenDatabase() != sql::INIT_OK)
     return;
 
   sql::Statement statement(db_.GetCachedStatement(
       SQL_FROM_HERE, "DELETE FROM images_by_url"));
   statement.Run();
 }
 
+int64 PersistentImageStore::GetStoreSize() {
+  // Ensure that the db is actually valid.
+  if (OpenDatabase() != sql::INIT_OK)

[sky, 2014/05/29 21:51:05]

Do you really need to open the db here?

[Kibeom Kim (inactive), 2014/05/29 23:07:15]

Done.

+    return -1;
+
+  return base::File(path_, base::File::FLAG_OPEN | base::File::FLAG_READ).
+      GetLength();
+}
+
 PersistentImageStore::~PersistentImageStore() {
   DCHECK(sequence_checker_.CalledOnValidSequencedThread());
 }
 
 sql::InitStatus PersistentImageStore::OpenDatabase() {
   DCHECK(sequence_checker_.CalledOnValidSequencedThread());
 
   if (db_.is_open())
     return sql::INIT_OK;
 
   const size_t kAttempts = 2;
 
   sql::InitStatus status = sql::INIT_FAILURE;
   for (size_t i = 0; i < kAttempts; ++i) {
     status = OpenDatabaseImpl(db_, path_);
     if (status == sql::INIT_OK)
       return status;
 
     // Can't open, raze().
     if (db_.is_open())
       db_.Raze();
     db_.Close();
   }
 
   DCHECK(false) << "Can't open image DB";
   return sql::INIT_FAILURE;
 }