[date] Refactor TimezoneCache to be separate from the OS

src/date.h

 // Copyright 2012 the V8 project 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 V8_DATE_H_
 #define V8_DATE_H_
 
 #include "src/allocation.h"
 #include "src/base/platform/platform.h"
+#include "src/base/timezone-cache.h"
 #include "src/globals.h"
 
-
 namespace v8 {
 namespace internal {
 
 class DateCache {
  public:
   static const int kMsPerMin = 60 * 1000;
   static const int kSecPerDay = 24 * 60 * 60;
   static const int64_t kMsPerDay = kSecPerDay * 1000;
   static const int64_t kMsPerMonth = kMsPerDay * 30;
 
@@ skipping 14 matching lines @@
   static const int kInvalidLocalOffsetInMs = kMaxInt;
   // Sentinel that denotes an invalid cache stamp.
   // It is an invariant of DateCache that cache stamp is non-negative.
   static const int kInvalidStamp = -1;
 
   DateCache() : stamp_(0), tz_cache_(base::OS::CreateTimezoneCache()) {
     ResetDateCache();
   }
 
   virtual ~DateCache() {
-    base::OS::DisposeTimezoneCache(tz_cache_);
+    delete tz_cache_;
     tz_cache_ = NULL;
   }
 
 
   // Clears cached timezone information and increments the cache stamp.
   void ResetDateCache();
 
 
   // Computes floor(time_ms / kMsPerDay).
   static int DaysFromTime(int64_t time_ms) {
@@ skipping 28 matching lines @@
       local_offset_ms_ = GetLocalOffsetFromOS();
     }
     return local_offset_ms_;
   }
 
 
   const char* LocalTimezone(int64_t time_ms) {
     if (time_ms < 0 || time_ms > kMaxEpochTimeInMs) {
       time_ms = EquivalentTime(time_ms);
     }
-    return base::OS::LocalTimezone(static_cast<double>(time_ms), tz_cache_);
+    return tz_cache_->LocalTimezone(static_cast<double>(time_ms));
   }
 
   // ECMA 262 - 15.9.5.26
   int TimezoneOffset(int64_t time_ms) {
     int64_t local_ms = ToLocal(time_ms);
     return static_cast<int>((time_ms - local_ms) / kMsPerMin);
   }
 
   // ECMA 262 - 15.9.1.9
   // LocalTime(t) = t + LocalTZA + DaylightSavingTA(t)
@@ skipping 90 matching lines @@
   // Cache stamp is used for invalidating caches in JSDate.
   // We increment the stamp each time when the timezone information changes.
   // JSDate objects perform stamp check and invalidate their caches if
   // their saved stamp is not equal to the current stamp.
   Smi* stamp() { return stamp_; }
   void* stamp_address() { return &stamp_; }
 
   // These functions are virtual so that we can override them when testing.
   virtual int GetDaylightSavingsOffsetFromOS(int64_t time_sec) {
     double time_ms = static_cast<double>(time_sec * 1000);
-    return static_cast<int>(
-        base::OS::DaylightSavingsOffset(time_ms, tz_cache_));
+    return static_cast<int>(tz_cache_->DaylightSavingsOffset(time_ms));
   }
 
   virtual int GetLocalOffsetFromOS() {
-    double offset = base::OS::LocalTimeOffset(tz_cache_);
+    double offset = tz_cache_->LocalTimeOffset();
     DCHECK(offset < kInvalidLocalOffsetInMs);
     return static_cast<int>(offset);
   }
 
  private:
   // The implementation relies on the fact that no time zones have
   // more than one daylight savings offset change per 19 days.
   // In Egypt in 2010 they decided to suspend DST during Ramadan. This
   // led to a short interval where DST is in effect from September 10 to
   // September 30.
@@ skipping 54 matching lines @@
   int ymd_month_;
   int ymd_day_;
 
   base::TimezoneCache* tz_cache_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif