[tracing] Support shared and private permission. (missing perm flag)

base/trace_event/process_memory_maps.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_PROCESS_MEMORY_MAPS_H_
 #define BASE_TRACE_EVENT_PROCESS_MEMORY_MAPS_H_
 
 #include <stdint.h>
 
 #include <string>
 #include <vector>
 
 #include "base/base_export.h"
 #include "base/macros.h"
 
 namespace base {
 namespace trace_event {
 
 class TracedValue;
 
 // Data model for process-wide memory stats.
 class BASE_EXPORT ProcessMemoryMaps {
  public:
   struct BASE_EXPORT VMRegion {
     static const uint32_t kProtectionFlagsRead;
     static const uint32_t kProtectionFlagsWrite;
     static const uint32_t kProtectionFlagsExec;
+    static const uint32_t kProtectionFlagsMayshare;
 
     VMRegion();
 
     uint64_t start_address;
     uint64_t size_in_bytes;
     uint32_t protection_flags;
     std::string mapped_file;
 
     // private_dirty_resident + private_clean_resident + shared_dirty_resident +
     // shared_clean_resident = resident set size.
@@ skipping 23 matching lines @@
  private:
   std::vector<VMRegion> vm_regions_;
 
   DISALLOW_COPY_AND_ASSIGN(ProcessMemoryMaps);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_PROCESS_MEMORY_MAPS_H_