Revert of [builtins] Introduce proper Float64Exp operator.

src/v8.cc

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