Implementation of TBMv2 blinkGcMetric in TBMv3 blink_gc_metric.

Validated using crrev.com/c/2692923 locally against one trace. Will run against
more and update this CL description with the results.

Relevant files for TBMv2 for review:
blinkGcMetric: https://github.com/catapult-project/catapult/blob/master/tracing/tracing/metrics/blink/gc_metric.html
Utility function: https://source.chromium.org/chromium/chromium/src/+/master:third_party/catapult/tracing/tracing/metrics/v8/utils.html

Bug: 178379929
Change-Id: Ieb8dccc41a07dbaff1c09247399620ed0ace6c8f
diff --git a/Android.bp b/Android.bp
index b68b134..c0efaeb 100644
--- a/Android.bp
+++ b/Android.bp
@@ -3658,6 +3658,7 @@
     "protos/perfetto/metrics/android/thread_time_in_state_metric.proto",
     "protos/perfetto/metrics/android/unsymbolized_frames.proto",
     "protos/perfetto/metrics/chrome/all_chrome_metrics.proto",
+    "protos/perfetto/metrics/chrome/blink_gc_metric.proto",
     "protos/perfetto/metrics/chrome/frame_times.proto",
     "protos/perfetto/metrics/chrome/reported_by_page.proto",
     "protos/perfetto/metrics/chrome/scroll_jank.proto",
@@ -7777,6 +7778,7 @@
     "src/trace_processor/metrics/chrome/scroll_jank_cause_get_bitmap.sql",
     "src/trace_processor/metrics/chrome/scroll_jank_cause_queuing_delay.sql",
     "src/trace_processor/metrics/chrome/test_chrome_metric.sql",
+    "src/trace_processor/metrics/experimental/blink_gc_metric.sql",
     "src/trace_processor/metrics/experimental/frame_times.sql",
     "src/trace_processor/metrics/experimental/reported_by_page.sql",
     "src/trace_processor/metrics/trace_metadata.sql",