Remove fb303 value of decision.skipped_unicast_route

Summary: When we introduced the feature knob of IPv4 route with IPv6 next hops, we also introduced `decision.skipped_unicast_route` counter, which is a fb303 value. However, once we have rolled out the `v4_over_v6` feature and it has been deployed everywhere, we do not need to monitor this `decision.skipped_unicast_route` anymore.

Reviewed By: xiangxu1121

Differential Revision: D53075672

fbshipit-source-id: 47c335b5b88d5b8d137306b948bf6e0a097bf30b

openr/decision/SpfSolver.cpp

@@ -97,8 +97,6 @@ SpfSolver::SpfSolver(
   fb303::fbData->addStatExportType("decision.skipped_mpls_route", fb303::COUNT);
   fb303::fbData->addStatExportType(
       "decision.duplicate_node_label", fb303::COUNT);
-  fb303::fbData->addStatExportType(
-      "decision.skipped_unicast_route", fb303::COUNT);
   fb303::fbData->addStatExportType("decision.spf_ms", fb303::AVG);
   fb303::fbData->addStatExportType("decision.spf_runs", fb303::COUNT);
   fb303::fbData->addStatExportType("decision.errors", fb303::COUNT);
@@ -174,8 +172,6 @@ SpfSolver::createRouteForPrefix(
                   << folly::IPAddress::networkToString(prefix)
                   << " while v4 is not enabled, and "
                   << "we are not allowing v4 prefix over v6 nexthop.";
-    fb303::fbData->addStatValue(
-        "decision.skipped_unicast_route", 1, fb303::COUNT);
     return std::nullopt;
   }
 

openr/decision/tests/DecisionTest.cpp

@@ -5937,7 +5937,6 @@ TEST_F(DecisionTestFixture, Counters) {
   EXPECT_EQ(counters.at("decision.num_prefixes"), 9);
   EXPECT_EQ(counters.at("decision.no_route_to_prefix.count.60"), 1);
   EXPECT_EQ(counters.at("decision.incompatible_forwarding_type.count.60"), 1);
-  EXPECT_EQ(counters.at("decision.skipped_unicast_route.count.60"), 0);
   EXPECT_EQ(counters.at("decision.skipped_mpls_route.count.60"), 1);
   EXPECT_EQ(counters.at("decision.no_route_to_label.count.60"), 1);