Heap profiler: allow returning aggregated snapshots via the new API.

include/v8-profiler.h

Index: include/v8-profiler.h
diff --git a/include/v8-profiler.h b/include/v8-profiler.h
index 9e3cb873c6fa7e2d2c43c50de32f6669bab9e3fe..dd1b8caf7b52303f906ff7786024410ec4b904b6 100644
--- a/include/v8-profiler.h
+++ b/include/v8-profiler.h
@@ -260,10 +260,17 @@ class V8EXPORT HeapGraphNode {
 
   /**
    * Returns node id. For the same heap object, the id remains the same
-   * across all snapshots.
+   * across all snapshots. Not applicable to aggregated heap snapshots
+   * as they only contain aggregated instances.
    */
   uint64_t GetId() const;
 
+  /**
+   * Returns the number of instances. Only applicable to aggregated
+   * heap snapshots.
+   */
+  int GetInstancesCount() const;
+
   /** Returns node's own size, in bytes. */
   int GetSelfSize() const;
 
@@ -313,6 +320,15 @@ class V8EXPORT HeapSnapshotsDiff {
  */
 class V8EXPORT HeapSnapshot {
  public:
+  enum Type {
+    kFull = 0,       // Heap snapshot with all instances and references.
+    kAggregated = 1  // Snapshot doesn't contain individual heap entries,
+                     //instead they are grouped by constructor name.
+  };
+
+  /** Returns heap snapshot type. */
+  Type GetType() const;
+
   /** Returns heap snapshot UID (assigned by the profiler.) */
   unsigned GetUid() const;
 
@@ -322,7 +338,10 @@ class V8EXPORT HeapSnapshot {
   /** Returns the root node of the heap graph. */
   const HeapGraphNode* GetRoot() const;
 
-  /** Returns a diff between this snapshot and another one. */
+  /**
+   * Returns a diff between this snapshot and another one. Only snapshots
+   * of the same type can be compared.
+   */
   const HeapSnapshotsDiff* CompareWith(const HeapSnapshot* snapshot) const;
 };
 
@@ -341,8 +360,13 @@ class V8EXPORT HeapProfiler {
   /** Returns a profile by uid. */
   static const HeapSnapshot* FindSnapshot(unsigned uid);
 
-  /** Takes a heap snapshot and returns it. Title may be an empty string. */
-  static const HeapSnapshot* TakeSnapshot(Handle<String> title);
+  /**
+   * Takes a heap snapshot and returns it. Title may be an empty string.
+   * See HeapSnapshot::Type for types description.
+   */
+  static const HeapSnapshot* TakeSnapshot(
+      Handle<String> title,
+      HeapSnapshot::Type type = HeapSnapshot::kFull);
 };