[tracing] Simplify design of MemoryAllocatorDump

base/trace_event/memory_dump_provider.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_MEMORY_DUMP_PROVIDER_H_
 #define BASE_TRACE_EVENT_MEMORY_DUMP_PROVIDER_H_
 
 #include "base/base_export.h"
 #include "base/memory/ref_counted.h"
-#include "base/trace_event/memory_allocator_attributes.h"
+#include "base/trace_event/memory_allocator_attributes_type_info.h"
 
 namespace base {
 
 class SingleThreadTaskRunner;
 
 namespace trace_event {
 
 class ProcessMemoryDump;
 
 // The contract interface that memory dump providers must implement.
 class BASE_EXPORT MemoryDumpProvider {
  public:
   // Called by the MemoryDumpManager when generating memory dumps.
   // Returns: true if the |pmd| was successfully populated, false otherwise.
   virtual bool DumpInto(ProcessMemoryDump* pmd) = 0;
 
   virtual const char* GetFriendlyName() const = 0;
 
-  const MemoryAllocatorDeclaredAttributes& allocator_attributes() const {
-    return allocator_attributes_;
+  const MemoryAllocatorAttributesTypeInfo& allocator_attributes_type_info()
+      const {
+    return allocator_attributes_type_info_;
   }
 
   // The dump provider can specify an optional thread affinity (in its
   // base constructor call). If |task_runner| is non empty, all the calls to
   // DumpInto are guaranteed to be posted to that TaskRunner.
   const scoped_refptr<SingleThreadTaskRunner>& task_runner() const {
     return task_runner_;
   }
 
  protected:
   // Default ctor: the MDP is not bound to any thread (must be a singleton).
   MemoryDumpProvider();
 
   // Use this ctor to ensure that DumpInto() is called always on the same thread
   // specified by |task_runner|.
   explicit MemoryDumpProvider(
       const scoped_refptr<SingleThreadTaskRunner>& task_runner);
 
   virtual ~MemoryDumpProvider();
 
-  void DeclareAllocatorAttribute(const MemoryAllocatorDeclaredAttribute& attr);
+  void DeclareAllocatorAttribute(const std::string& allocator_name,
+                                 const std::string& attribute_name,
+                                 const std::string& attribute_type);
 
  private:
-  // The map (attribute name -> type) that specifies the semantic of the
-  // extra attributes that the MemoryAllocatorDump(s) produced by this
-  // MemoryDumpProvider will have.
-  MemoryAllocatorDeclaredAttributes allocator_attributes_;
+  // A map of attributes types (declared through DeclareAllocatorAttribute())
+  // emitted by this allocator dumper.
+  MemoryAllocatorAttributesTypeInfo allocator_attributes_type_info_;
 
   // (Optional) TaskRunner on which the DumpInfo call should be posted.
-  const scoped_refptr<SingleThreadTaskRunner> task_runner_;
+  scoped_refptr<SingleThreadTaskRunner> task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(MemoryDumpProvider);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_MEMORY_DUMP_PROVIDER_H_