IndexedDB: Fix prefetching; cache was always being bypassed.

content/common/indexed_db/proxy_webidbcursor_impl.cc

 // Copyright (c) 2012 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 "content/common/indexed_db/proxy_webidbcursor_impl.h"
 
 #include "content/common/child_thread.h"
 #include "content/common/indexed_db/indexed_db_messages.h"
 #include "content/common/indexed_db/indexed_db_dispatcher.h"
 
@@ skipping 44 matching lines @@
 void RendererWebIDBCursorImpl::update(const WebSerializedScriptValue& value,
                                       WebIDBCallbacks* callbacks,
                                       WebExceptionCode& ec) {
   IndexedDBDispatcher* dispatcher =
       IndexedDBDispatcher::ThreadSpecificInstance();
   dispatcher->RequestIDBCursorUpdate(
       content::SerializedScriptValue(value), callbacks, idb_cursor_id_, &ec);
 }
 
 void RendererWebIDBCursorImpl::continueFunction(const WebIDBKey& key,
-                                                WebIDBCallbacks* callbacks,
+                                                WebIDBCallbacks* callbacks_ptr,
                                                 WebExceptionCode& ec) {
   IndexedDBDispatcher* dispatcher =
       IndexedDBDispatcher::ThreadSpecificInstance();
+  scoped_ptr<WebIDBCallbacks> callbacks(callbacks_ptr);

[michaeln, 2012/03/17 02:44:46]

lgtm

 
-  if (key.type() == WebIDBKey::InvalidType) {
+  if (key.type() == WebIDBKey::NullType) {
     // No key, so this would qualify for a prefetch.
     ++continue_count_;
 
     if (!prefetch_keys_.empty()) {
       // We have a prefetch cache, so serve the result from that.
-      CachedContinue(callbacks);
+      CachedContinue(callbacks.get());
       return;
     }
 
     if (continue_count_ > kPrefetchContinueThreshold) {
       // Request pre-fetch.
-      dispatcher->RequestIDBCursorPrefetch(prefetch_amount_, callbacks,
+      dispatcher->RequestIDBCursorPrefetch(prefetch_amount_,
+                                           callbacks.release(),
                                            idb_cursor_id_, &ec);
 
       // Increase prefetch_amount_ exponentially.
       prefetch_amount_ *= 2;
       if (prefetch_amount_ > kMaxPrefetchAmount)
         prefetch_amount_ = kMaxPrefetchAmount;
 
       return;
     }
   } else {
     // Key argument supplied. We couldn't prefetch this.
     ResetPrefetchCache();
   }
 
-  dispatcher->RequestIDBCursorContinue(IndexedDBKey(key), callbacks,
+  dispatcher->RequestIDBCursorContinue(IndexedDBKey(key), callbacks.release(),
                                        idb_cursor_id_, &ec);
 }
 
 void RendererWebIDBCursorImpl::deleteFunction(WebIDBCallbacks* callbacks,
                                               WebExceptionCode& ec) {
   IndexedDBDispatcher* dispatcher =
       IndexedDBDispatcher::ThreadSpecificInstance();
   dispatcher->RequestIDBCursorDelete(callbacks, idb_cursor_id_, &ec);
 }
 
@@ skipping 64 matching lines @@
       IndexedDBDispatcher::ThreadSpecificInstance();
   dispatcher->RequestIDBCursorPrefetchReset(used_prefetches_,
                                             prefetch_keys_.size(),
                                             idb_cursor_id_);
   prefetch_keys_.clear();
   prefetch_primary_keys_.clear();
   prefetch_values_.clear();
 
   pending_onsuccess_callbacks_ = 0;
 }