Remove uid and title from HeapSnapshot

None of these fields is used in Blink. Embedder always can implement them using existing API.

BUG=chromium:465651
LOG=Y

Review URL: https://codereview.chromium.org/983833006

Cr-Commit-Position: refs/heads/master@{#27113}

include/v8-profiler.h

@@ -313,12 +313,6 @@ class V8_EXPORT HeapSnapshot {
     kJSON = 0  // See format description near 'Serialize' method.
   };
 
-  /** Returns heap snapshot UID (assigned by the profiler.) */
-  unsigned GetUid() const;
-
-  /** Returns heap snapshot title. */
-  Handle<String> GetTitle() const;
-
   /** Returns the root node of the heap graph. */
   const HeapGraphNode* GetRoot() const;
 
@@ -367,7 +361,8 @@ class V8_EXPORT HeapSnapshot {
    * Nodes reference strings, other nodes, and edges by their indexes
    * in corresponding arrays.
    */
-  void Serialize(OutputStream* stream, SerializationFormat format) const;
+  void Serialize(OutputStream* stream,
+                 SerializationFormat format = kJSON) const;
 };
 
 
@@ -452,13 +447,19 @@ class V8_EXPORT HeapProfiler {
   };
 
   /**
-   * Takes a heap snapshot and returns it. Title may be an empty string.
+   * Takes a heap snapshot and returns it. Title parameter is deprecated and
+   * should be an empty string.
+   * TODO: deprecate this method.
    */
   const HeapSnapshot* TakeHeapSnapshot(
       Handle<String> title,
       ActivityControl* control = NULL,
       ObjectNameResolver* global_object_name_resolver = NULL);
 
+  const HeapSnapshot* TakeHeapSnapshot(
+      ActivityControl* control = NULL,
+      ObjectNameResolver* global_object_name_resolver = NULL);
+
   /**
    * Starts tracking of heap objects population statistics. After calling
    * this method, all heap objects relocations done by the garbage collector

src/api.cc

@@ -7620,18 +7620,6 @@ void HeapSnapshot::Delete() {
 }
 
 
-unsigned HeapSnapshot::GetUid() const {
-  return ToInternal(this)->uid();
-}
-
-
-Handle<String> HeapSnapshot::GetTitle() const {
-  i::Isolate* isolate = i::Isolate::Current();
-  return ToApiHandle<String>(
-      isolate->factory()->InternalizeUtf8String(ToInternal(this)->title()));
-}
-
-
 const HeapGraphNode* HeapSnapshot::GetRoot() const {
   return reinterpret_cast<const HeapGraphNode*>(ToInternal(this)->root());
 }
@@ -7711,9 +7699,15 @@ const HeapSnapshot* HeapProfiler::TakeHeapSnapshot(
     Handle<String> title,
     ActivityControl* control,
     ObjectNameResolver* resolver) {
+  return TakeHeapSnapshot(control, resolver);
+}
+
+
+const HeapSnapshot* HeapProfiler::TakeHeapSnapshot(
+    ActivityControl* control, ObjectNameResolver* resolver) {
   return reinterpret_cast<const HeapSnapshot*>(
-      reinterpret_cast<i::HeapProfiler*>(this)->TakeSnapshot(
-          *Utils::OpenHandle(*title), control, resolver));
+      reinterpret_cast<i::HeapProfiler*>(this)
+          ->TakeSnapshot(control, resolver));
 }
 
 

src/heap-profiler.cc

@@ -15,7 +15,6 @@ namespace internal {
 HeapProfiler::HeapProfiler(Heap* heap)
     : ids_(new HeapObjectsMap(heap)),
       names_(new StringsStorage(heap)),
-      next_snapshot_uid_(1),
       is_tracking_object_moves_(false) {
 }
 
@@ -63,10 +62,9 @@ v8::RetainedObjectInfo* HeapProfiler::ExecuteWrapperClassCallback(
 
 
 HeapSnapshot* HeapProfiler::TakeSnapshot(
-    const char* name,
     v8::ActivityControl* control,
     v8::HeapProfiler::ObjectNameResolver* resolver) {
-  HeapSnapshot* result = new HeapSnapshot(this, name, next_snapshot_uid_++);
+  HeapSnapshot* result = new HeapSnapshot(this);
   {
     HeapSnapshotGenerator generator(result, control, resolver, heap());
     if (!generator.GenerateSnapshot()) {
@@ -82,14 +80,6 @@ HeapSnapshot* HeapProfiler::TakeSnapshot(
 }
 
 
-HeapSnapshot* HeapProfiler::TakeSnapshot(
-    String* name,
-    v8::ActivityControl* control,
-    v8::HeapProfiler::ObjectNameResolver* resolver) {
-  return TakeSnapshot(names_->GetName(name), control, resolver);
-}
-
-
 void HeapProfiler::StartHeapObjectsTracking(bool track_allocations) {
   ids_->UpdateHeapObjectsMap();
   is_tracking_object_moves_ = true;

src/heap-profiler.h

@@ -22,11 +22,6 @@ class HeapProfiler {
   size_t GetMemorySizeUsedByProfiler();
 
   HeapSnapshot* TakeSnapshot(
-      const char* name,
-      v8::ActivityControl* control,
-      v8::HeapProfiler::ObjectNameResolver* resolver);
-  HeapSnapshot* TakeSnapshot(
-      String* name,
       v8::ActivityControl* control,
       v8::HeapProfiler::ObjectNameResolver* resolver);
 
@@ -73,7 +68,6 @@ class HeapProfiler {
   SmartPointer<HeapObjectsMap> ids_;
   List<HeapSnapshot*> snapshots_;
   SmartPointer<StringsStorage> names_;
-  unsigned next_snapshot_uid_;
   List<v8::HeapProfiler::WrapperInfoCallback> wrapper_callbacks_;
   SmartPointer<AllocationTracker> allocation_tracker_;
   bool is_tracking_object_moves_;

src/heap-snapshot-generator.cc

@@ -178,12 +178,8 @@ template <> struct SnapshotSizeConstants<8> {
 }  // namespace
 
 
-HeapSnapshot::HeapSnapshot(HeapProfiler* profiler,
-                           const char* title,
-                           unsigned uid)
+HeapSnapshot::HeapSnapshot(HeapProfiler* profiler)
     : profiler_(profiler),
-      title_(title),
-      uid_(uid),
       root_index_(HeapEntry::kNoEntry),
       gc_roots_index_(HeapEntry::kNoEntry),
       max_snapshot_js_object_id_(0) {
@@ -2883,12 +2879,7 @@ void HeapSnapshotJSONSerializer::SerializeNodes() {
 
 
 void HeapSnapshotJSONSerializer::SerializeSnapshot() {
-  writer_->AddString("\"title\":\"");
-  writer_->AddString(snapshot_->title());
-  writer_->AddString("\"");
-  writer_->AddString(",\"uid\":");
-  writer_->AddNumber(snapshot_->uid());
-  writer_->AddString(",\"meta\":");
+  writer_->AddString("\"meta\":");
   // The object describing node serialization layout.
   // We use a set of macros to improve readability.
 #define JSON_A(s) "[" s "]"

src/heap-snapshot-generator.h

@@ -141,14 +141,10 @@ class HeapEntry BASE_EMBEDDED {
 // HeapSnapshotGenerator fills in a HeapSnapshot.
 class HeapSnapshot {
  public:
-  HeapSnapshot(HeapProfiler* profiler,
-               const char* title,
-               unsigned uid);
+  explicit HeapSnapshot(HeapProfiler* profiler);
   void Delete();
 
   HeapProfiler* profiler() { return profiler_; }
-  const char* title() { return title_; }
-  unsigned uid() { return uid_; }
   size_t RawSnapshotSize() const;
   HeapEntry* root() { return &entries_[root_index_]; }
   HeapEntry* gc_roots() { return &entries_[gc_roots_index_]; }
@@ -181,8 +177,6 @@ class HeapSnapshot {
   HeapEntry* AddGcSubrootEntry(int tag, SnapshotObjectId id);
 
   HeapProfiler* profiler_;
-  const char* title_;
-  unsigned uid_;
   int root_index_;
   int gc_roots_index_;
   int gc_subroot_indexes_[VisitorSynchronization::kNumberOfSyncTags];