Use VM tag in profile and add stack trace trie

runtime/vm/service.cc

Index: runtime/vm/service.cc
diff --git a/runtime/vm/service.cc b/runtime/vm/service.cc
index 1903e4ba01f2e05987a094fc62aabccc950988f2..583b79f0192a4077e0d84d07d910e454f46519e7 100644
--- a/runtime/vm/service.cc
+++ b/runtime/vm/service.cc
@@ -1310,7 +1310,12 @@ static bool HandleProfile(Isolate* isolate, JSONStream* js) {
   // A full profile includes disassembly of all Dart code objects.
   // TODO(johnmccutchan): Add sub command to trigger full code dump.
   bool full_profile = false;
-  Profiler::PrintToJSONStream(isolate, js, full_profile);
+  const char* tags_option = js->LookupOption("tags");
+  bool use_tags = true;
+  if ((tags_option != NULL) && (strcmp("hide", tags_option) == 0)) {
+    use_tags = false;
+  }

[turnidge, 2014/03/17 21:19:31]

Does it make sense to do any unit testing of this part of the change?

Are you sure you want to accept weird values of "tags" here?  (like
tags=jfdkljkldfjlsd)

[Cutch, 2014/03/18 14:39:19]

Added a unit test for the profile command and an error case when the tags option
value isn't "hide".

+  Profiler::PrintToJSONStream(isolate, js, full_profile, use_tags);
   return true;
 }