[date] Properly handle timezones with non-ASCII characters.

src/builtins.cc

Index: src/builtins.cc
diff --git a/src/builtins.cc b/src/builtins.cc
index d2d641560754a8ce56da283c5cf81a4f8556b441..d34d6c2c9787af3c26b226fdf8eea020c4b98943 100644
--- a/src/builtins.cc
+++ b/src/builtins.cc
@@ -2750,7 +2750,11 @@ BUILTIN(DateConstructor) {
   char buffer[128];
   Vector<char> str(buffer, arraysize(buffer));
   ToDateString(time_val, str, isolate->date_cache());
-  return *isolate->factory()->NewStringFromAsciiChecked(str.start());
+  Handle<String> result;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, result,
+      isolate->factory()->NewStringFromUtf8(CStrVector(buffer)));
+  return *result;
 }
 
 
@@ -3330,7 +3334,11 @@ BUILTIN(DatePrototypeToDateString) {
   char buffer[128];
   Vector<char> str(buffer, arraysize(buffer));
   ToDateString(date->value()->Number(), str, isolate->date_cache(), kDateOnly);
-  return *isolate->factory()->NewStringFromAsciiChecked(str.start());
+  Handle<String> result;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, result,
+      isolate->factory()->NewStringFromUtf8(CStrVector(buffer)));
+  return *result;
 }
 
 
@@ -3370,7 +3378,11 @@ BUILTIN(DatePrototypeToString) {
   char buffer[128];
   Vector<char> str(buffer, arraysize(buffer));
   ToDateString(date->value()->Number(), str, isolate->date_cache());
-  return *isolate->factory()->NewStringFromAsciiChecked(str.start());
+  Handle<String> result;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, result,
+      isolate->factory()->NewStringFromUtf8(CStrVector(buffer)));
+  return *result;
 }
 
 
@@ -3381,7 +3393,11 @@ BUILTIN(DatePrototypeToTimeString) {
   char buffer[128];
   Vector<char> str(buffer, arraysize(buffer));
   ToDateString(date->value()->Number(), str, isolate->date_cache(), kTimeOnly);
-  return *isolate->factory()->NewStringFromAsciiChecked(str.start());
+  Handle<String> result;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
+      isolate, result,
+      isolate->factory()->NewStringFromUtf8(CStrVector(buffer)));
+  return *result;
 }