Fix CryptoService to work with CompositeByteBuf

[justinlin-linkedin]

PutOperation would read multiple ByteBuf as a Composite from NettyServer layer. If the blob should be encrypted, then the crypto service has to work with CompositeByteBuf. This PR adds such support.

[cgtz]

LGTM

[codecov-io]

Codecov Report

Merging #1323 into master will decrease coverage by 0.08%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master    #1323      +/-   ##
============================================
- Coverage     72.16%   72.08%   -0.09%     
+ Complexity     6536     6533       -3     
============================================
  Files           478      478              
  Lines         37330    37374      +44     
  Branches       4714     4722       +8     
============================================
+ Hits          26941    26942       +1     
- Misses         9142     9174      +32     
- Partials       1247     1258      +11

Impacted Files	Coverage Δ	Complexity Δ
...ls/src/main/java/com.github.ambry.utils/Utils.java	77.24% <100%> (+0.34%)	116 <2> (+2)	⬆️
...java/com.github.ambry.router/GCMCryptoService.java	89.31% <100%> (+1.48%)	18 <0> (+4)	⬆️
...in/java/com.github.ambry/router/CryptoService.java	100% <100%> (+100%)	4 <4> (+4)	⬆️
...b.ambry.clustermap/StaticClusterAgentsFactory.java	33.33% <0%> (-6.67%)	4% <0%> (ø)
...ry.replication/CloudToStoreReplicationManager.java	53.42% <0%> (-3.62%)	10% <0%> (ø)
...b.ambry.network/BlockingChannelConnectionPool.java	73.68% <0%> (-2.11%)	11% <0%> (-1%)
.../main/java/com.github.ambry.store/ScanResults.java	81.25% <0%> (-1.57%)	16% <0%> (-1%)
.../java/com.github.ambry.router/DeleteOperation.java	93.43% <0%> (-1.46%)	44% <0%> (-1%)
...in/java/com.github.ambry.store/BlobStoreStats.java	71.25% <0%> (-1.25%)	103% <0%> (-2%)
...m.github.ambry.replication/ReplicationMetrics.java	94.97% <0%> (-1.2%)	43% <0%> (-1%)
... and 10 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update a8014eb...1ebcde7. Read the comment docs.