Fix missing objects.

language-agent-v2/JVMMetric.proto

@@ -26,7 +26,7 @@ import "common/common.proto";
 import "common/JVM.proto";
 
 service JVMMetricReportService {
-    rpc collect (JVMMetrics) returns (Downstream) {
+    rpc collect (JVMMetricCollection) returns (Commands) {
     }
 }
 

language-agent-v2/trace.proto

@@ -25,7 +25,7 @@ option csharp_namespace = "SkyWalking.NetworkProtocol";
 import "common/common.proto";
 
 service TraceSegmentReportService {
-    rpc collect (stream UpstreamSegment) returns (Downstream) {
+    rpc collect (stream UpstreamSegment) returns (Commands) {
     }
 }
 

language-agent/JVMMetricsService.proto

@@ -29,3 +29,8 @@ service JVMMetricsService {
     rpc collect (JVMMetrics) returns (Downstream) {
     }
 }
+
+message JVMMetrics {
+    repeated JVMMetric metrics = 1;
+    int32 applicationInstanceId = 2;
+}