[turbofan] Constant propagation for JumpIfFalse/JumpIfTrue.

src/code-stub-assembler.cc

Index: src/code-stub-assembler.cc
diff --git a/src/code-stub-assembler.cc b/src/code-stub-assembler.cc
index ad0dd093eafa0fd8c629bdbd854504c596dff425..441b3ff36035de596d2f6b4bf4fd1d803a4e0844 100644
--- a/src/code-stub-assembler.cc
+++ b/src/code-stub-assembler.cc
@@ -2968,6 +2968,10 @@ Node* CodeStubAssembler::IsWeakCell(Node* object) {
   return HasInstanceType(object, WEAK_CELL_TYPE);
 }
 
+Node* CodeStubAssembler::IsBoolean(Node* object) {
+  return IsBooleanMap(LoadMap(object));
+}
+
 Node* CodeStubAssembler::IsName(Node* object) {
   return Int32LessThanOrEqual(LoadInstanceType(object),
                               Int32Constant(LAST_NAME_TYPE));