Drop support for recording Dart objects in a timeline trace

runtime/vm/timeline.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_TIMELINE_H_
 #define VM_TIMELINE_H_
 
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
 
@@ skipping 178 matching lines @@
     return recorder_;
   }
 
   // TODO(johnmccutchan): Disallow setting recorder after Init?
   void set_recorder(TimelineEventRecorder* recorder) {
     recorder_ = recorder;
   }
 
   // Records an event. Will return |NULL| if not enabled. The returned
   // |TimelineEvent| is in an undefined state and must be initialized.
-  // |obj| is associated with the returned |TimelineEvent|.
-  TimelineEvent* StartEvent(const Object& obj);
-
-  // Records an event. Will return |NULL| if not enabled. The returned
-  // |TimelineEvent| is in an undefined state and must be initialized.
   TimelineEvent* StartEvent();
 
   void CompleteEvent(TimelineEvent* event);
 
   int64_t GetNextSeq();
 
  private:
   TimelineEventRecorder* recorder_;
   const char* name_;
   bool enabled_;
@@ skipping 169 matching lines @@
 
   // Interface method(s) which must be implemented.
   virtual void PrintJSON(JSONStream* js) = 0;
   virtual TimelineEventBlock* GetNewBlock() = 0;
   virtual TimelineEventBlock* GetHeadBlock() = 0;
 
   void WriteTo(const char* directory);
 
  protected:
   // Interface method(s) which must be implemented.
-  virtual void VisitObjectPointers(ObjectPointerVisitor* visitor) = 0;
-  virtual TimelineEvent* StartEvent(const Object& object) = 0;
   virtual TimelineEvent* StartEvent() = 0;
   virtual void CompleteEvent(TimelineEvent* event) = 0;
 
   // Utility method(s).
   void PrintJSONMeta(JSONArray* array) const;
   TimelineEvent* ThreadBlockStartEvent();
 
   Mutex lock_;
 
   friend class TimelineEventBlockIterator;
   friend class TimelineStream;
   friend class TimelineTestHelper;
   friend class Isolate;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TimelineEventRecorder);
 };
 
 
 // A recorder that stores events in a ring buffer of fixed capacity.
-// This recorder does track Dart objects.
 class TimelineEventRingRecorder : public TimelineEventRecorder {
  public:
   static const intptr_t kDefaultCapacity = 8192;
 
   explicit TimelineEventRingRecorder(intptr_t capacity = kDefaultCapacity);
   ~TimelineEventRingRecorder();
 
   void PrintJSON(JSONStream* js);
   TimelineEventBlock* GetNewBlock();
   TimelineEventBlock* GetHeadBlock();
 
  protected:
-  void VisitObjectPointers(ObjectPointerVisitor* visitor);
-  TimelineEvent* StartEvent(const Object& object);
   TimelineEvent* StartEvent();
   void CompleteEvent(TimelineEvent* event);
 
   intptr_t FindOldestBlockIndex() const;
   TimelineEventBlock* GetNewBlockLocked();
 
   void PrintJSONEvents(JSONArray* array) const;
 
   TimelineEventBlock** blocks_;
   RawArray* event_objects_;
   intptr_t capacity_;
   intptr_t num_blocks_;
   intptr_t block_cursor_;
 };
 
 
 // An abstract recorder that calls |StreamEvent| whenever an event is complete.
-// This recorder does not track Dart objects.
 class TimelineEventStreamingRecorder : public TimelineEventRecorder {
  public:
   TimelineEventStreamingRecorder();
   ~TimelineEventStreamingRecorder();
 
   void PrintJSON(JSONStream* js);
   TimelineEventBlock* GetNewBlock() {
     return NULL;
   }
   TimelineEventBlock* GetHeadBlock() {
     return NULL;
   }
 
   // Called when |event| is ready to be streamed. It is unsafe to keep a
   // reference to |event| as it may be freed as soon as this function returns.
   virtual void StreamEvent(TimelineEvent* event) = 0;
 
  protected:
-  void VisitObjectPointers(ObjectPointerVisitor* visitor);
-  TimelineEvent* StartEvent(const Object& object);
   TimelineEvent* StartEvent();
   void CompleteEvent(TimelineEvent* event);
 };
 
 
 // A recorder that stores events in chains of blocks of events.
-// This recorder does not track Dart objects.
 // NOTE: This recorder will continue to allocate blocks until it exhausts
 // memory.
 class TimelineEventEndlessRecorder : public TimelineEventRecorder {
  public:
   TimelineEventEndlessRecorder();
 
   // Acquire a new block of events.
   // Takes a lock.
   // Recorder owns the block and it should be filled by only one thread.
   TimelineEventBlock* GetNewBlock();
 
   TimelineEventBlock* GetHeadBlock();
 
   // It is expected that this function is only called when an isolate is
   // shutting itself down.
   // NOTE: Calling this while threads are filling in their blocks is not safe
   // and there are no checks in place to ensure that doesn't happen.
   // TODO(koda): Add isolate count to |ThreadRegistry| and verify that it is 1.
   void PrintJSON(JSONStream* js);
 
  protected:
-  void VisitObjectPointers(ObjectPointerVisitor* visitor);
-  TimelineEvent* StartEvent(const Object& object);
   TimelineEvent* StartEvent();
   void CompleteEvent(TimelineEvent* event);
 
   TimelineEventBlock* GetNewBlockLocked();
   void PrintJSONEvents(JSONArray* array) const;
 
   // Useful only for testing. Only works for one thread.
   void Clear();
 
   TimelineEventBlock* head_;
@@ skipping 18 matching lines @@
   TimelineEventBlock* Next();
 
  private:
   TimelineEventBlock* current_;
   TimelineEventRecorder* recorder_;
 };
 
 }  // namespace dart
 
 #endif  // VM_TIMELINE_H_