Add ProcessMetrics::CreateCurrentProcessMetrics() method.

base/process/process_metrics.h

 // Copyright (c) 2013 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.
 
 // This file contains routines for gathering resource statistics for processes
 // running on the system.
 
 #ifndef BASE_PROCESS_PROCESS_METRICS_H_
 #define BASE_PROCESS_PROCESS_METRICS_H_
 
@@ skipping 72 matching lines @@
   CommittedKBytes() : priv(0), mapped(0), image(0) {}
   size_t priv;
   size_t mapped;
   size_t image;
 };
 
 // Convert a POSIX timeval to microseconds.
 BASE_EXPORT int64 TimeValToMicroseconds(const struct timeval& tv);
 
 // Provides performance metrics for a specified process (CPU usage, memory and
-// IO counters). To use it, invoke CreateProcessMetrics() to get an instance
-// for a specific process, then access the information with the different get
+// IO counters). Use CreateCurrentProcessMetrics() to get an instance for the
+// current process, or CreateProcessMetrics() to get an instance for an
+// arbitrary process. Then, access the information with the different get
 // methods.
 class BASE_EXPORT ProcessMetrics {
  public:
   ~ProcessMetrics();
 
   // Creates a ProcessMetrics for the specified process.
   // The caller owns the returned object.
 #if !defined(OS_MACOSX) || defined(OS_IOS)
   static ProcessMetrics* CreateProcessMetrics(ProcessHandle process);
 #else
 
   // The port provider needs to outlive the ProcessMetrics object returned by
   // this function. If NULL is passed as provider, the returned object
   // only returns valid metrics if |process| is the current process.
   static ProcessMetrics* CreateProcessMetrics(ProcessHandle process,
                                               PortProvider* port_provider);
 #endif  // !defined(OS_MACOSX) || defined(OS_IOS)
 
+  // Creates a ProcessMetrics for the current process. This a cross-platform
+  // convenience wrapper for CreateProcessMetrics().
+  // The caller owns the returned object.
+  static ProcessMetrics* CreateCurrentProcessMetrics();
+
   // Returns the current space allocated for the pagefile, in bytes (these pages
   // may or may not be in memory).  On Linux, this returns the total virtual
   // memory size.
   size_t GetPagefileUsage() const;
   // Returns the peak space allocated for the pagefile, in bytes.
   size_t GetPeakPagefileUsage() const;
   // Returns the current working set size, in bytes.  On Linux, this returns
   // the resident set size.
   size_t GetWorkingSetSize() const;
   // Returns the peak working set size, in bytes.
@@ skipping 271 matching lines @@
   SystemDiskInfo disk_info_;
 #endif
 #if defined(OS_CHROMEOS)
   SwapInfo swap_info_;
 #endif
 };
 
 }  // namespace base
 
 #endif  // BASE_PROCESS_PROCESS_METRICS_H_