Last remaining bits of my append branch that didn't fit elsewhere in JIRA (just misc cleanup)
- Slight cleanup to recoverFile() function in TFA4
- Improve error messages on OP_READ_BLOCK
- Some comment cleanup in FSNamesystem
- Remove toInodeUnderConstruction (not used)
- Add some checks for null blocks to avoid NPE
- Only log "inconsistent size" warnings at WARN level for non-under-construction blocks.
- Redundant addStoredBlock calls are also not worthy of WARN level
- Add some extra information to a warning in ReplicationTargetChooser
This may need
HDFS-1057 to be committed first to apply.