Make callers of FromUTC(Local)Exploded in net/ use new time API.

net/disk_cache/blockfile/eviction.cc

 // 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.
 
 // The eviction policy is a very simple pure LRU, so the elements at the end of
 // the list are evicted until kCleanUpMargin free space is available. There is
 // only one list in use (Rankings::NO_USE), and elements are sent to the front
 // of the list whenever they are accessed.
 
 // The new (in-development) eviction policy adds re-use as a factor to evict
@@ skipping 257 matching lines @@
     if (header_->lru.filled)
       return;
 
     header_->lru.filled = 1;
 
     if (header_->create_time) {
       // This is the first entry that we have to evict, generate some noise.
       backend_->FirstEviction();
     } else {
       // This is an old file, but we may want more reports from this user so
-      // lets save some create_time.
-      Time::Exploded old = {0};
-      old.year = 2009;
-      old.month = 3;
-      old.day_of_month = 1;
-      header_->create_time = Time::FromLocalExploded(old).ToInternalValue();
+      // lets save some create_time. Conversion cannot fail here.
+      const base::Time time_2009_3_1 =
+          base::Time::FromInternalValue(12985574400000000);
+      header_->create_time = time_2009_3_1.ToInternalValue();

[eroman, 2016/10/27 21:44:34]

For the record -- this is a bit different from what was happening before (it is
now using a fixed time stamp, whereas before it was using a timestamp based on
the user's timezone).

However I believe using a fixed timestamp as being done now is the correct
approach.

Also I wonder if we should simplify this to:

// 2009/03/01 (midnight UTC)
header_->create_time = 12985574400000000;

.. But on the other h and the documentation for |create_time| is pretty bad and
mentions nothing about the granularity or epoch of the timestamp, so perhaps
just using base::Time's "internal value" as you have done here is more
consistent with the surrounding code.

[maksims (do not use this acc), 2016/11/29 07:38:56]

Ok, thanks. Let it be like this.

     }
   }
 }
 
 Rankings::List Eviction::GetListForEntry(EntryImpl* entry) {
   return Rankings::NO_USE;
 }
 
 bool Eviction::EvictEntry(CacheRankingsBlock* node, bool empty,
                           Rankings::List list) {
@@ skipping 305 matching lines @@
               Time::FromInternalValue(last2.get()->Data()->last_used));
   if (last3.get())
     CACHE_UMA(AGE, "HighUseAge", 0,
               Time::FromInternalValue(last3.get()->Data()->last_used));
   if (last4.get())
     CACHE_UMA(AGE, "DeletedAge", 0,
               Time::FromInternalValue(last4.get()->Data()->last_used));
 }
 
 }  // namespace disk_cache