Integrate stats builder into field writer (facebookincubator#444)

Summary:
Pull Request resolved: facebookincubator#444

Use the stats builder to collect stats in field writer for the respective writer types, replacing the current stats. Additionally fixing:
* missing key stats in Flatmaps
* wrong value stats attribution
* thread safety in chunking write paths

Notably we also added a thread safe wrapper for flatmap value writers to merge their stats concurrently for now, to be extended to collect separate feature/map stats later. Collecting separate streams right now and merging later is additional costs in both wall time and memory that we don't need to pay unless one wants feature/map stats.

NOTE: this diff currently disables the physical aggregation, and it will be fully restored with the diff replacing it with the new physical aggregation call sites.

Reviewed By: helfman

Differential Revision: D90166052

fbshipit-source-id: 87b7b1b7fc6c1c9682383fd446a0a52bd6cf8165

Author: Huameng (Michael) Jiang

dwio/nimble/velox/CMakeLists.txt

@@ -66,6 +66,8 @@ add_library(
 )
 target_link_libraries(
   nimble_velox_field_writer
+  nimble_column_stats
+  nimble_column_stats_utils
   nimble_velox_schema
   nimble_velox_stream_data
   nimble_velox_schema_builder
@@ -172,8 +174,9 @@ add_library(
 )
 target_link_libraries(
   nimble_velox_writer
-  nimble_common
+  nimble_column_stats
   nimble_column_stats_utils
+  nimble_common
   nimble_encodings
   nimble_index
   nimble_tablet_writer