Use stricter type checking in UMA_HISTOGRAM_ENUMERATION

base/debug/activity_tracker.cc

 // Copyright 2016 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.
 
 #include "base/debug/activity_tracker.h"
 
 #include <algorithm>
 #include <limits>
 #include <utility>
 
@@ skipping 1353 matching lines @@
   DCHECK_LE(stack_memory_size_, allocator_->GetAllocSize(mem_reference));
 
   // Create a tracker with the acquired memory and set it as the tracker
   // for this particular thread in thread-local-storage.
   ManagedActivityTracker* tracker =
       new ManagedActivityTracker(mem_reference, mem_base, stack_memory_size_);
   DCHECK(tracker->IsValid());
   this_thread_tracker_.Set(tracker);
   int old_count = thread_tracker_count_.fetch_add(1, std::memory_order_relaxed);
 
-  UMA_HISTOGRAM_ENUMERATION("ActivityTracker.ThreadTrackers.Count",
-                            old_count + 1, kMaxThreadCount);
+  UMA_HISTOGRAM_EXACT_LINEAR("ActivityTracker.ThreadTrackers.Count",
+                             old_count + 1, static_cast<int>(kMaxThreadCount));
   return tracker;
 }
 
 void GlobalActivityTracker::ReleaseTrackerForCurrentThreadForTesting() {
   ThreadActivityTracker* tracker =
       reinterpret_cast<ThreadActivityTracker*>(this_thread_tracker_.Get());
   if (tracker) {
     this_thread_tracker_.Set(nullptr);
     delete tracker;
   }
@@ skipping 397 matching lines @@
     : GlobalActivityTracker::ScopedThreadActivity(
           program_counter,
           nullptr,
           Activity::ACT_PROCESS_WAIT,
           ActivityData::ForProcess(process->Pid()),
           /*lock_allowed=*/true) {}
 #endif
 
 }  // namespace debug
 }  // namespace base