Revert of [tracing] Adding task information to heap profiler

base/trace_event/heap_profiler_allocation_context_tracker.h

 // Copyright 2015 The Chromium 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 BASE_TRACE_EVENT_HEAP_PROFILER_ALLOCATION_CONTEXT_TRACKER_H_
 #define BASE_TRACE_EVENT_HEAP_PROFILER_ALLOCATION_CONTEXT_TRACKER_H_
 
 #include <vector>
 
 #include "base/atomicops.h"
@@ skipping 40 matching lines @@
   // Set the thread name in the AllocationContextTracker of current thread if
   // capture is enabled.
   static void SetCurrentThreadName(const char* name);
 
   // Pushes a frame onto the thread-local pseudo stack.
   void PushPseudoStackFrame(StackFrame frame);
 
   // Pops a frame from the thread-local pseudo stack.
   void PopPseudoStackFrame(StackFrame frame);
 
-  // Push and pop current task's context. A stack is used to support nested
-  // tasks and the top of the stack will be used in allocation context.
-  void PushCurrentTaskContext(const char* context);
-  void PopCurrentTaskContext(const char* context);
-
   // Returns a snapshot of the current thread-local context.
   AllocationContext GetContextSnapshot();
 
   ~AllocationContextTracker();
 
  private:
   AllocationContextTracker();
 
   static subtle::Atomic32 capture_enabled_;
 
   // The pseudo stack where frames are |TRACE_EVENT| names.
   std::vector<StackFrame> pseudo_stack_;
 
   // The thread name is used as the first entry in the pseudo stack.
   const char* thread_name_;
 
-  // Stack of tasks' contexts. Context serves as a different dimension than
-  // pseudo stack to cluster allocations.
-  std::vector<const char*> task_contexts_;
-
   DISALLOW_COPY_AND_ASSIGN(AllocationContextTracker);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_HEAP_PROFILER_ALLOCATION_CONTEXT_TRACKER_H_