Fix removed block zero size log reporting

`memSize` and `diskSize` of **removed** block will always report as 0.0 B, like this:
    
    INFO BlockManagerMasterActor$BlockManagerInfo:Removed input-2-1377741792200 on xxx in memory (size: 0.0 B, free: 2.8 GB)

Cause input parameter `memSize` and `diskSize` calculated in BlockManager will always be zero. It would be better to display the actual size of this block when reporting this log.

Thanks
Jerry