[builtins] Introduce proper Float64Exp operator.

src/v8.cc

Index: src/v8.cc
diff --git a/src/v8.cc b/src/v8.cc
index 6a7aaab0628c99776e01a276845d587cdf264d98..d660b58c1096d9e08b372d609076b48ca1ed316b 100644
--- a/src/v8.cc
+++ b/src/v8.cc
@@ -45,7 +45,6 @@ void V8::TearDown() {
   Bootstrapper::TearDownExtensions();
   ElementsAccessor::TearDown();
   LOperand::TearDownCaches();
-  ExternalReference::TearDownMathExpData();
   RegisteredExtension::UnregisterAll();
   Isolate::GlobalTearDown();
   sampler::Sampler::TearDown();