Support profiler code transition tags

runtime/vm/profiler_service.h

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_PROFILER_SERVICE_H_
 #define VM_PROFILER_SERVICE_H_
 
 #include "vm/allocation.h"
 #include "vm/code_observers.h"
 #include "vm/globals.h"
@@ skipping 282 matching lines @@
     return (kind == kExclusiveCode) || (kind == kInclusiveCode);
   }
 
   static bool IsFunctionTrie(TrieKind kind) {
     return !IsCodeTrie(kind);
   }
 
   explicit Profile(Isolate* isolate);
 
   // Build a filtered model using |filter| with the specified |tag_order|.
-  void Build(SampleFilter* filter, TagOrder tag_order);
+  void Build(SampleFilter* filter, TagOrder tag_order, intptr_t extra_tags = 0);
 
   // After building:
   int64_t min_time() const { return min_time_; }
   int64_t max_time() const { return max_time_; }
   int64_t GetTimeSpan() const {
     return max_time() - min_time();
   }
   intptr_t sample_count() const { return sample_count_; }
 
   ProfileFunction* GetFunction(intptr_t index);
@@ skipping 50 matching lines @@
  private:
   Profile* profile_;
   ProfileTrieNode* parent_;
   ProfileTrieNode* current_;
   bool code_trie_;
 };
 
 
 class ProfilerService : public AllStatic {
  public:
+  enum {
+    kCodeTransitionTagsBit = (1 << 0),
+  };
+
   static void PrintJSON(JSONStream* stream,
-                        Profile::TagOrder tag_order);
+                        Profile::TagOrder tag_order,
+                        intptr_t extra_tags);
 
   static void PrintAllocationJSON(JSONStream* stream,
                                   Profile::TagOrder tag_order,
                                   const Class& cls);
 
   static void ClearSamples();
 
  private:
   static void PrintJSONImpl(Isolate* isolate,
                             JSONStream* stream,
                             Profile::TagOrder tag_order,
+                            intptr_t extra_tags,
                             SampleFilter* filter);
 };
 
 }  // namespace dart
 
 #endif  // VM_PROFILER_SERVICE_H_