IndexedDB: Recycle curosr objects when calling continue().

This is the Chromium side of https://bugs.webkit.org/show_bug.cgi?id=71115

Instead of creating a new IDBCursor wrapper each time continue() is called,
we should instead send back a new onSuccessCursorContinue() callback, and the
IDBRequest will know which cursor to return.

This patch implements the new callback.

For performance, we piggy-pick the cursor's current key, primary key and
value with the callback. To be able to do this, the IndexedDBDispatcherHost
must keep track of which cursor corresponds to which pending callback.

The IndexedDBDispatcher keeps the key, primary key and value cached
for each cursor.

BUG=98685
TEST=all current tests pass


Review URL: http://codereview.chromium.org/8400061

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@108788 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 6 insertions, 0 deletions

diff --git a/content/common/indexed_db_messages.h b/content/common/indexed_db_messages.h
index 03bb03a..4830f0e 100644
--- a/content/common/indexed_db_messages.h
+++ b/content/common/indexed_db_messages.h
@@ -147,6 +147,12 @@ IPC_MESSAGE_CONTROL5(IndexedDBMsg_CallbacksSuccessIDBCursor,
                      IndexedDBKey /* key */,
                      IndexedDBKey /* primary key */,
                      content::SerializedScriptValue /* script_value */)
+IPC_MESSAGE_CONTROL5(IndexedDBMsg_CallbacksSuccessCursorContinue,
+                     int32 /* response_id */,
+                     int32 /* cursor_id */,
+                     IndexedDBKey /* key */,
+                     IndexedDBKey /* primary key */,
+                     content::SerializedScriptValue /* script_value */)
 IPC_MESSAGE_CONTROL2(IndexedDBMsg_CallbacksSuccessIDBDatabase,
                      int32 /* response_id */,
                      int32 /* idb_database_id */)