[#1364] Increase BLOCKS_METADATA_BUFFER_SIZE

- Closes #1364
- Filed another related improvement issue #1555
- Changelog update

CHANGELOG.md

@@ -14,6 +14,9 @@ and this library adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   `onCriticalErrorHandler` in case any error occurs 
 - Block synchronization logic now works above batch of blocks with size 1000 blocks instead of just 100 blocks 
   except the Zcash sandblasting period in which batch size of 100 blocks is still used
+- The internal `FileCompactBlockRepository.BLOCKS_METADATA_BUFFER_SIZE` constant has been raised from 10 to 1000 to 
+  match the block synchronization batch size. The overall speed-up of the entire block synchronization logic is about 
+  50%.
 - Checkpoints update
 
 ### Fixed

sdk-lib/src/main/java/cash/z/ecc/android/sdk/internal/storage/block/FileCompactBlockRepository.kt

@@ -125,10 +125,14 @@ internal class FileCompactBlockRepository(
          */
         const val BLOCK_FILENAME_SUFFIX = "-compactblock"
 
+        // TODO [#1555]: Keep BLOCKS_METADATA_BUFFER_SIZE the same as current SYNC_BATCH_SIZE
+        // TODO [#1555]: https://github.com/Electric-Coin-Company/zcash-android-wallet-sdk/issues/1555
         /**
          * The size of block meta data buffer
+         *
+         * Note: we should keep this size as close as possible to [CompactBlockProcessor.SYNC_BATCH_SIZE]
          */
-        const val BLOCKS_METADATA_BUFFER_SIZE = 10
+        const val BLOCKS_METADATA_BUFFER_SIZE = 1000
 
         /**
          * @param blockCacheRoot The root directory for the compact block cache (contains the database and a