profiler: cleanup unused alternate_timer code

base/tracked_objects.h

 // Copyright (c) 2012 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_TRACKED_OBJECTS_H_
 #define BASE_TRACKED_OBJECTS_H_
 
 #include <stdint.h>
 
 #include <map>
 #include <set>
 #include <stack>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/atomicops.h"
 #include "base/base_export.h"
 #include "base/containers/hash_tables.h"
 #include "base/gtest_prod_util.h"
 #include "base/lazy_instance.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/process/process_handle.h"
-#include "base/profiler/alternate_timer.h"
 #include "base/profiler/tracked_time.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_checker.h"
 #include "base/threading/thread_local_storage.h"
 
 namespace base {
 struct TrackingInfo;
 }
 
 // TrackedObjects provides a database of stats about objects (generally Tasks)
@@ skipping 403 matching lines @@
   // Current allowable states of the tracking system.  The states can vary
   // between ACTIVE and DEACTIVATED, but can never go back to UNINITIALIZED.
   enum Status {
     UNINITIALIZED,         // Pristine, link-time state before running.
     DORMANT_DURING_TESTS,  // Only used during testing.
     DEACTIVATED,           // No longer recording profiling.
     PROFILING_ACTIVE,      // Recording profiles.
     STATUS_LAST = PROFILING_ACTIVE
   };
 
+  typedef unsigned int NowFunction();  // Type for an alternate timer function.

[Ilya Sherman, 2016/01/28 01:36:47]

Why is this needed?

[Primiano Tucci (use gerrit), 2016/01/28 10:46:36]

This was previously in alternate_timer.h, which I am now removing.
The code below needs this.

[Ilya Sherman, 2016/01/29 01:23:14]

Is it just used for testing?  If so, let's not expose it as part of the public
API.

[Primiano Tucci (use gerrit), 2016/02/01 13:34:19]

Good point. Just testing. Done.

   typedef base::hash_map<Location, Births*, Location::Hash> BirthMap;
   typedef std::map<const Births*, DeathData> DeathMap;
 
   // Initialize the current thread context with a new instance of ThreadData.
   // This is used by all threads that have names, and should be explicitly
   // set *before* any births on the threads have taken place.  It is generally
   // only used by the message loop, which has a well defined thread name.
   static void InitializeThreadContext(const std::string& suggested_name);
 
   // Using Thread Local Store, find the current instance for collecting data.
@@ skipping 359 matching lines @@
   ProcessDataSnapshot();
   ~ProcessDataSnapshot();
 
   PhasedProcessDataSnapshotMap phased_snapshots;
   base::ProcessId process_id;
 };
 
 }  // namespace tracked_objects
 
 #endif  // BASE_TRACKED_OBJECTS_H_