Update from https://crrev.com/333737

base/trace_event/memory_allocator_dump.h

Index: base/trace_event/memory_allocator_dump.h
diff --git a/base/trace_event/memory_allocator_dump.h b/base/trace_event/memory_allocator_dump.h
index 1bb27f952e1a0be5202980efa94b3dbb90fbaa1b..9a151a6f9c5e2df0960b1b56745ab1914bd539d8 100644
--- a/base/trace_event/memory_allocator_dump.h
+++ b/base/trace_event/memory_allocator_dump.h
@@ -8,6 +8,7 @@
 #include "base/base_export.h"
 #include "base/basictypes.h"
 #include "base/logging.h"
+#include "base/trace_event/memory_allocator_dump_guid.h"
 #include "base/values.h"
 
 namespace base {
@@ -22,9 +23,15 @@ class BASE_EXPORT MemoryAllocatorDump {
  public:
   // MemoryAllocatorDump is owned by ProcessMemoryDump.
   MemoryAllocatorDump(const std::string& absolute_name,
+                      ProcessMemoryDump* process_memory_dump,
+                      const MemoryAllocatorDumpGuid& guid);
+  MemoryAllocatorDump(const std::string& absolute_name,
                       ProcessMemoryDump* process_memory_dump);
   ~MemoryAllocatorDump();
 
+  // Standard attribute name to model allocated space.
+  static const char kNameSize[];
+
   // Standard attribute name to model total space requested by the allocator
   // (e.g., amount of pages requested to the system).
   static const char kNameOuterSize[];
@@ -56,6 +63,7 @@ class BASE_EXPORT MemoryAllocatorDump {
 
   // Helper setter for scalar attributes.
   void AddScalar(const std::string& name, const char* units, uint64 value);
+  void AddScalarF(const std::string& name, const char* units, double value);
   void AddString(const std::string& name,
                  const char* units,
                  const std::string& value);
@@ -68,10 +76,19 @@ class BASE_EXPORT MemoryAllocatorDump {
     return process_memory_dump_;
   }
 
+  // |guid| is an optional global dump identifier, unique across all processes
+  // within the scope of a global dump. It is only required when using the
+  // graph APIs (see TODO_method_name) to express retention / suballocation or
+  // cross process sharing. See crbug.com/492102 for design docs.
+  // Subsequent MemoryAllocatorDump(s) with the same |absolute_name| are
+  // expected to have the same guid.
+  const MemoryAllocatorDumpGuid& guid() const { return guid_; }
+
  private:
   const std::string absolute_name_;
   ProcessMemoryDump* const process_memory_dump_;  // Not owned (PMD owns this).
   DictionaryValue attributes_;
+  MemoryAllocatorDumpGuid guid_;
 
   DISALLOW_COPY_AND_ASSIGN(MemoryAllocatorDump);
 };