Revert of [runtime] Introduce dedicated JSBoundFunction to represent bound functions.

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index 5200ab4413234414a20d8de43163893da7da81f3..f5b324a364ea6c7aaee2b181b98461267373d1b7 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -2509,6 +2509,15 @@
   // Ensure that {function} has an instance prototype.
   __ testb(FieldOperand(function_map, Map::kBitFieldOffset),
            Immediate(1 << Map::kHasNonInstancePrototype));
+  __ j(not_zero, &slow_case);
+
+  // Ensure that {function} is not bound.
+  Register const shared_info = kScratchRegister;
+  __ movp(shared_info,
+          FieldOperand(function, JSFunction::kSharedFunctionInfoOffset));
+  __ TestBitSharedFunctionInfoSpecialField(
+      shared_info, SharedFunctionInfo::kCompilerHintsOffset,
+      SharedFunctionInfo::kBoundFunction);
   __ j(not_zero, &slow_case);
 
   // Get the "prototype" (or initial map) of the {function}.