remove the checking for new operation
fix SyncAdd done flag memory corruption problem
release top-level protocol resource at destructor
add thread checking for every VD function
fix VsyncTickTask() comment
provide the direct call for add/remove in ObserverListHelper
Bug 987529 - integrate refresh driver into vsync dispatcher
fix software timer to call vsync dispatcher directly
add software vsync timer support
add a flag to stop tick immediately for refresh driver timer StopTimer()
fix the rename of VsyncTick(). we use VsyncTickTask() now.
fix async/sync usage for Observer list helper interface change