[api,profiler] Introduce GetRetainerInfos callback for profiling

include/v8-profiler.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_V8_PROFILER_H_
 #define V8_V8_PROFILER_H_
 
+#include <unordered_set>
 #include <vector>
 #include "v8.h"  // NOLINT(build/include)
 
 /**
  * Profiler support for the V8 JavaScript engine.
  */
 namespace v8 {
 
 class HeapGraphNode;
 struct HeapStatsUpdate;
@@ skipping 605 matching lines @@
  * Interface for controlling heap profiling. Instance of the
  * profiler can be retrieved using v8::Isolate::GetHeapProfiler.
  */
 class V8_EXPORT HeapProfiler {
  public:
   enum SamplingFlags {
     kSamplingNoFlags = 0,
     kSamplingForceGC = 1 << 0,
   };
 
+  typedef std::unordered_set<const v8::PersistentBase<v8::Value>*>
+      RetainerChildren;
+  typedef std::vector<std::pair<v8::RetainedObjectInfo*, RetainerChildren>>
+      RetainerGroups;
+  typedef std::vector<std::pair<const v8::PersistentBase<v8::Value>*,
+                                const v8::PersistentBase<v8::Value>*>>
+      RetainerEdges;
+
+  struct RetainerInfos {
+    RetainerGroups groups;
+    RetainerEdges edges;
+  };
+
+  /**
+   * Callback function invoked to retrieve all RetainerInfos from the embedder.
+   */
+  typedef RetainerInfos (*GetRetainerInfosCallback)(v8::Isolate* isolate);
+
   /**
    * Callback function invoked for obtaining RetainedObjectInfo for
    * the given JavaScript wrapper object. It is prohibited to enter V8
    * while the callback is running: only getters on the handle and
    * GetPointerFromInternalField on the objects are allowed.
    */
   typedef RetainedObjectInfo* (*WrapperInfoCallback)(uint16_t class_id,
                                                      Local<Value> wrapper);
 
   /** Returns the number of snapshots taken. */
@@ skipping 132 matching lines @@
    * Deletes all snapshots taken. All previously returned pointers to
    * snapshots and their contents become invalid after this call.
    */
   void DeleteAllHeapSnapshots();
 
   /** Binds a callback to embedder's class ID. */
   void SetWrapperClassInfoProvider(
       uint16_t class_id,
       WrapperInfoCallback callback);
 
+  void SetGetRetainerInfosCallback(GetRetainerInfosCallback callback);
+
   /**
    * Default value of persistent handle class ID. Must not be used to
    * define a class. Can be used to reset a class of a persistent
    * handle.
    */
   static const uint16_t kPersistentHandleNoClassId = 0;
 
   /** Returns memory used for profiler internal data and snapshots. */
   size_t GetProfilerMemorySize();
 
@@ skipping 93 matching lines @@
   uint32_t index;  // Index of the time interval that was changed.
   uint32_t count;  // New value of count field for the interval with this index.
   uint32_t size;  // New value of size field for the interval with this index.
 };
 
 
 }  // namespace v8
 
 
 #endif  // V8_V8_PROFILER_H_