Fix memory leak in CPU Profile page

runtime/vm/profiler.h

 // Copyright (c) 2013, 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_H_
 #define VM_PROFILER_H_
 
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
 #include "vm/code_observers.h"
@@ skipping 280 matching lines @@
   }
 
   bool missing_frame_inserted() const {
     return MissingFrameInsertedBit::decode(state_);
   }
 
   void set_missing_frame_inserted(bool missing_frame_inserted) {
     state_ = MissingFrameInsertedBit::update(missing_frame_inserted, state_);
   }
 
+  bool truncated_trace() const {
+    return TruncatedTraceBit::decode(state_);
+  }
+
+  void set_truncated_trace(bool truncated_trace) {
+    state_ = TruncatedTraceBit::update(truncated_trace, state_);
+  }
+
   static void InitOnce();
 
   static intptr_t instance_size() {
     return instance_size_;
   }
 
   uword* GetPCArray() const;
 
   static const int kStackBufferSizeInWords = 2;
   uword* GetStackBuffer() {
     return &stack_buffer_[0];
   }
 
  private:
   static intptr_t instance_size_;
   static intptr_t pcs_length_;
   enum StateBits {
     kProcessedBit = 0,
     kLeafFrameIsDartBit = 1,
     kIgnoreBit = 2,
     kExitFrameBit = 3,
     kMissingFrameInsertedBit = 4,
+    kTruncatedTrace = 5,
   };
   class ProcessedBit : public BitField<bool, kProcessedBit, 1> {};
   class LeafFrameIsDart : public BitField<bool, kLeafFrameIsDartBit, 1> {};
   class IgnoreBit : public BitField<bool, kIgnoreBit, 1> {};
   class ExitFrameBit : public BitField<bool, kExitFrameBit, 1> {};
   class MissingFrameInsertedBit
     : public BitField<bool, kMissingFrameInsertedBit, 1> {};
+  class TruncatedTraceBit : public BitField<bool, kTruncatedTrace, 1> {};
+
   int64_t timestamp_;
   ThreadId tid_;
   Isolate* isolate_;
   uword pc_marker_;
   uword stack_buffer_[kStackBufferSizeInWords];
   uword vm_tag_;
   uword user_tag_;
   uword sp_;
   uword fp_;
   uword lr_;
@@ skipping 58 matching lines @@
   intptr_t capacity_;
   uintptr_t cursor_;
 
   DISALLOW_COPY_AND_ASSIGN(SampleBuffer);
 };
 
 
 }  // namespace dart
 
 #endif  // VM_PROFILER_H_