X87: [runtime] Introduce dedicated JSBoundFunction to represent bound functions.

src/x87/macro-assembler-x87.h

Index: src/x87/macro-assembler-x87.h
diff --git a/src/x87/macro-assembler-x87.h b/src/x87/macro-assembler-x87.h
index dfd63a6e8af90e3cbb83a030d09e6b1ff3f78e36..5a6bc7abff6080552a08663d6bce3c0898f3da60 100644
--- a/src/x87/macro-assembler-x87.h
+++ b/src/x87/macro-assembler-x87.h
@@ -513,6 +513,10 @@ class MacroAssembler: public Assembler {
   // Abort execution if argument is not a JSFunction, enabled via --debug-code.
   void AssertFunction(Register object);
 
+  // Abort execution if argument is not a JSBoundFunction,
+  // enabled via --debug-code.
+  void AssertBoundFunction(Register object);
+
   // Abort execution if argument is not undefined or an AllocationSite, enabled
   // via --debug-code.
   void AssertUndefinedOrAllocationSite(Register object);