[intrinsics] Remove %_IsFunction inline intrinsic.

src/crankshaft/hydrogen.cc

Index: src/crankshaft/hydrogen.cc
diff --git a/src/crankshaft/hydrogen.cc b/src/crankshaft/hydrogen.cc
index 8974355d0b751353aabc96a17edfd0715a3af08e..79bbbc34e231ad9b68dd0765dcd43d9bef0c48f3 100644
--- a/src/crankshaft/hydrogen.cc
+++ b/src/crankshaft/hydrogen.cc
@@ -12230,16 +12230,6 @@ void HOptimizedGraphBuilder::GenerateIsJSReceiver(CallRuntime* call) {
 }
 
 
-void HOptimizedGraphBuilder::GenerateIsFunction(CallRuntime* call) {
-  DCHECK(call->arguments()->length() == 1);
-  CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
-  HValue* value = Pop();
-  HHasInstanceTypeAndBranch* result = New<HHasInstanceTypeAndBranch>(
-      value, FIRST_FUNCTION_TYPE, LAST_FUNCTION_TYPE);
-  return ast_context()->ReturnControl(result, call->id());
-}
-
-
 void HOptimizedGraphBuilder::GenerateIsMinusZero(CallRuntime* call) {
   DCHECK(call->arguments()->length() == 1);
   CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));