document.lastModified should consider user's local time zone

Source/core/html/forms/TimeInputType.cpp

Index: Source/core/html/forms/TimeInputType.cpp
diff --git a/Source/core/html/forms/TimeInputType.cpp b/Source/core/html/forms/TimeInputType.cpp
index f91bf233176d4331c7c43d1bfc2845e2a8e4b20d..4319e63fc0fb3a4e3560e4721780e2151e918b37 100644
--- a/Source/core/html/forms/TimeInputType.cpp
+++ b/Source/core/html/forms/TimeInputType.cpp
@@ -73,12 +73,7 @@ const AtomicString& TimeInputType::formControlType() const
 
 Decimal TimeInputType::defaultValueForStepUp() const
 {
-    double current = currentTimeMS();
-    double utcOffset = calculateUTCOffset();
-    double dstOffset = calculateDSTOffset(current, utcOffset);
-    int offset = static_cast<int>((utcOffset + dstOffset) / msPerMinute);
-    current += offset * msPerMinute;
-
+    double current = convertToLocalTime(currentTimeMS());
     DateComponents date;
     date.setMillisecondsSinceMidnight(current);
     double milliseconds = date.millisecondsSinceEpoch();