Revert change to EquivalentTime in date.js. The checks that I've removed in...

Revert change to EquivalentTime in date.js. The checks that I've removed in the last changed were essential after all.

Review URL: http://codereview.chromium.org/660375

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3999 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/date-delay.js

@@ -114,9 +114,7 @@ function EquivalentTime(t) {
   // the actual year if it is in the range 1970..2037
   if (t >= 0 && t <= 2.1e12) return t;
 
-  // We call the function from runtime.cc directly to avoid extra checks which
-  // are unneeded.
-  var day = %DateMakeDay(EquivalentYear(YEAR_FROM_TIME(t)),
+  var day = MakeDay(EquivalentYear(YEAR_FROM_TIME(t)),
                     MONTH_FROM_TIME(t),
                     DATE_FROM_TIME(t));
   return MakeDate(day, TimeWithinDay(t));

src/runtime.cc

@@ -4961,6 +4961,9 @@ static Object* Runtime_DateMakeDay(Arguments args) {
     month += 12;
   }
 
+  ASSERT(month >= 0);
+  ASSERT(month < 12);
+
   static const int base_day = 365*1969 + 1969/4 - 1969/100 + 1969/400;
   int year1 = year - 1;
   int day_from_year = 365 * year1 + year1 / 4 - year1 / 100 + year1 / 400 -