The MLGDeviceD3D11, CompositorD3D11 and TextureClient use the same synchronization mechanism.
Create the new SyncObjectClient/Host types for reusing code.
Add SyncObject.cpp/h and create two new data types: SyncObjectClient and SyncObjectHost.
The SyncObjectClient is used for the TextureClient synchronization at client side.
The SyncObjectHost is used for the TextureHost synchronization in renderers such
as MLGDeviceD3D11 and CompositorD3D11.
MozReview-Commit-ID: 3l56WK1aZ15
JerryShih