trace_processor: add RowMap implementation and tests

This will be used in the remainder of the trace processor refactor
to perform efficient filtering.

Bug: 135177627
Change-Id: I222dcf23745d487747e31f5a2e2c95c02ffe0ddb
diff --git a/Android.bp b/Android.bp
index 3895a4b..5a42b36 100644
--- a/Android.bp
+++ b/Android.bp
@@ -3754,6 +3754,7 @@
     "src/trace_processor/counter_definitions_table.cc",
     "src/trace_processor/counter_values_table.cc",
     "src/trace_processor/db/bit_vector.cc",
+    "src/trace_processor/db/row_map.cc",
     "src/trace_processor/event_tracker.cc",
     "src/trace_processor/filtered_row_index.cc",
     "src/trace_processor/forwarding_trace_parser.cc",
@@ -3927,6 +3928,7 @@
     "src/trace_processor/counter_definitions_table.cc",
     "src/trace_processor/counter_values_table.cc",
     "src/trace_processor/db/bit_vector.cc",
+    "src/trace_processor/db/row_map.cc",
     "src/trace_processor/event_tracker.cc",
     "src/trace_processor/filtered_row_index.cc",
     "src/trace_processor/forwarding_trace_parser.cc",