Produce more useful stack traces for heap profiling.

base/trace_event/heap_profiler_allocation_context.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_H_
 #define BASE_TRACE_EVENT_HEAP_PROFILER_ALLOCATION_CONTEXT_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 51 matching lines @@
   const void* value;
 };
 
 bool BASE_EXPORT operator < (const StackFrame& lhs, const StackFrame& rhs);
 bool BASE_EXPORT operator == (const StackFrame& lhs, const StackFrame& rhs);
 bool BASE_EXPORT operator != (const StackFrame& lhs, const StackFrame& rhs);
 
 struct BASE_EXPORT Backtrace {
   Backtrace();
 
-  // If the stack is higher than what can be stored here, the bottom frames
-  // (the ones closer to main()) are stored. Depth of 12 is enough for most
+  // If the stack is higher than what can be stored here, the top frames
+  // (the ones further from main()) are stored. Depth of 12 is enough for most
   // pseudo traces (see above), but not for native traces, where we need more.
   enum { kMaxFrameCount = 48 };
   StackFrame frames[kMaxFrameCount];
   size_t frame_count;
 };
 
 bool BASE_EXPORT operator==(const Backtrace& lhs, const Backtrace& rhs);
 bool BASE_EXPORT operator!=(const Backtrace& lhs, const Backtrace& rhs);
 
 // The |AllocationContext| is context metadata that is kept for every allocation
@@ skipping 39 matching lines @@
 };
 
 template <>
 struct BASE_EXPORT hash<base::trace_event::AllocationContext> {
   size_t operator()(const base::trace_event::AllocationContext& context) const;
 };
 
 }  // namespace std
 
 #endif  // BASE_TRACE_EVENT_HEAP_PROFILER_ALLOCATION_CONTEXT_H_