Expose memory allocator internal stats and properties.

base/allocator/allocator_extension.h

Index: base/allocator/allocator_extension.h
diff --git a/base/allocator/allocator_extension.h b/base/allocator/allocator_extension.h
index b71fffe421b40859dd5c90c2ee02e2bb0894f5aa..dda0fd9dcfb40f6c53783a6a952ec428c4e5ab06 100644
--- a/base/allocator/allocator_extension.h
+++ b/base/allocator/allocator_extension.h
@@ -5,6 +5,8 @@
 #ifndef BASE_ALLOCATOR_ALLOCATOR_EXTENSION_H
 #define BASE_ALLOCATOR_ALLOCATOR_EXTENSION_H
 
+#include <stddef.h> // for size_t
+
 #include "base/allocator/allocator_extension_thunks.h"
 #include "base/base_export.h"
 #include "build/build_config.h"
@@ -12,6 +14,14 @@
 namespace base {
 namespace allocator {
 
+// Request the allocator to report value of its internal state variable.
+//
+// |name| name of the variable
+// |value| pointer to the returned value, must be not NULL.
+// Returns true if the value has been returned, false if a variable with such
+// name does not exist.
+BASE_EXPORT bool GetProperty(const char* name, size_t* value);
+
 // Request that the allocator print a human-readable description of the current
 // state of the allocator into a null-terminated string in the memory segment
 // buffer[0,buffer_length-1].
@@ -33,11 +43,15 @@ BASE_EXPORT void ReleaseFreeMemory();
 // No threading promises are made.  The caller is responsible for making sure
 // these pointers are set before any other threads attempt to call the above
 // functions.
+BASE_EXPORT void SetGetPropertyFunction(
+    thunks::GetPropertyFunction get_property_function);
+
 BASE_EXPORT void SetGetStatsFunction(
-    thunks::GetStatsFunction* get_stats_function);
+    thunks::GetStatsFunction get_stats_function);
 
 BASE_EXPORT void SetReleaseFreeMemoryFunction(
-    thunks::ReleaseFreeMemoryFunction* release_free_memory_function);
+    thunks::ReleaseFreeMemoryFunction release_free_memory_function);
+
 }  // namespace allocator
 }  // namespace base