Use PlatformThreadId, not int when dealing with thread ids.

base/stats_table.cc

Index: base/stats_table.cc
diff --git a/base/stats_table.cc b/base/stats_table.cc
index 1f2545795f0a78dbf4e9aa622bec5d55e6186257..31570b50b96c4618f1f274af3d1b65f8cea765b6 100644
--- a/base/stats_table.cc
+++ b/base/stats_table.cc
@@ -126,7 +126,7 @@ class StatsTablePrivate {
     return &thread_names_table_[
       (slot_id-1) * (StatsTable::kMaxThreadNameLength)];
   }
-  int* thread_tid(int slot_id) const {
+  PlatformThreadId* thread_tid(int slot_id) const {
     return &(thread_tid_table_[slot_id-1]);
   }
   int* thread_pid(int slot_id) const {
@@ -155,7 +155,7 @@ class StatsTablePrivate {
   base::SharedMemory shared_memory_;
   TableHeader* table_header_;
   char* thread_names_table_;
-  int* thread_tid_table_;
+  PlatformThreadId* thread_tid_table_;
   int* thread_pid_table_;
   char* counter_names_table_;
   int* data_table_;
@@ -217,7 +217,7 @@ void StatsTablePrivate::ComputeMappedPointers(void* memory) {
             max_threads() * StatsTable::kMaxThreadNameLength;
   offset += AlignOffset(offset);
 
-  thread_tid_table_ = reinterpret_cast<int*>(data + offset);
+  thread_tid_table_ = reinterpret_cast<PlatformThreadId*>(data + offset);
   offset += sizeof(int) * max_threads();
   offset += AlignOffset(offset);