Revert r10908 due to flakiness and crashes.

src/platform-nullos.cc

Index: src/platform-nullos.cc
diff --git a/src/platform-nullos.cc b/src/platform-nullos.cc
index e05345c80a3966aff84e8666c94482fb46d013ef..918327a983a3c2ab89c786d5224d121cbb7c45b4 100644
--- a/src/platform-nullos.cc
+++ b/src/platform-nullos.cc
@@ -55,30 +55,6 @@ double modulo(double x, double y) {
 }
 
 
-double fast_sin(double x) {
-  UNIMPLEMENTED();
-  return 0;
-}
-
-
-double fast_cos(double x) {
-  UNIMPLEMENTED();
-  return 0;
-}
-
-
-double fast_tan(double x) {
-  UNIMPLEMENTED();
-  return 0;
-}
-
-
-double fast_log(double x) {
-  UNIMPLEMENTED();
-  return 0;
-}
-
-
 // Initialize OS class early in the V8 startup.
 void OS::SetUp() {
   // Seed the random number generator.