Generate better branch code for instanceof-predicates.

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
===================================================================
--- src/hydrogen-instructions.cc	(revision 8287)
+++ src/hydrogen-instructions.cc	(working copy)
@@ -1579,6 +1579,21 @@
 }
 
 
+HType HInstanceOf::CalculateInferredType() {
+  return HType::Boolean();
+}
+
+
+HType HDeleteProperty::CalculateInferredType() {
+  return HType::Boolean();
+}
+
+
+HType HInstanceOfKnownGlobal::CalculateInferredType() {
+  return HType::Boolean();
+}
+
+
 HType HBitwiseBinaryOperation::CalculateInferredType() {
   return HType::TaggedNumber();
 }