Ensure that service protocol specification and implementation use the correct numeric types

runtime/vm/service.cc

Index: runtime/vm/service.cc
diff --git a/runtime/vm/service.cc b/runtime/vm/service.cc
index 1dc403b15ffc2cfc67d5c998bb0dd50447365932..3d28748bc6a606c3c24e39795101eb1d8932dd8d 100644
--- a/runtime/vm/service.cc
+++ b/runtime/vm/service.cc
@@ -2942,10 +2942,7 @@ static bool GetVM(Isolate* isolate, JSONStream* js) {
   jsobj.AddProperty("targetCPU", CPU::Id());
   jsobj.AddProperty("hostCPU", HostCPUFeatures::hardware());
   jsobj.AddProperty("version", Version::String());
-  // Send pid as a string because it allows us to avoid any issues with
-  // pids > 53-bits (when consumed by JavaScript).
-  // TODO(johnmccutchan): Codify how integers are sent across the service.
-  jsobj.AddPropertyF("pid", "%" Pd "", OS::ProcessId());
+  jsobj.AddProperty("pid", OS::ProcessId());
   jsobj.AddProperty("_assertsEnabled", isolate->flags().asserts());
   jsobj.AddProperty("_typeChecksEnabled", isolate->flags().type_checks());
   int64_t start_time_millis = (Dart::vm_isolate()->start_time() /