Set the current context to the function's context when entering to LAP.

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 84630928d49ee3a256af73a9a2268d49e029d49c..e01bf5b7c176e773af36598539132372220957fe 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -2755,14 +2755,22 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // holder
   __ Push(holder);
 
-  __ movp(scratch, rsp);
-  // Push return address back on stack.
-  __ PushReturnAddressFrom(return_address);
-
-  if (!this->is_lazy()) {
+#if 0  // TEMPORARILY COMMENTED OUT: MOVED TO
+       // PropertyHandlerCompiler::GenerateApiAccessorCall
+  if (this->is_lazy()) {
+    // load context from holder
+    __ movp(scratch, FieldOperand(holder, HeapObject::kMapOffset));
+    __ GetMapConstructor(scratch, scratch, context);
+    __ movp(context, FieldOperand(scratch, JSFunction::kContextOffset));
+  } else {
     // load context from callee
     __ movp(context, FieldOperand(callee, JSFunction::kContextOffset));
   }
+#endif
+
+  __ movp(scratch, rsp);
+  // Push return address back on stack.
+  __ PushReturnAddressFrom(return_address);
 
   // Allocate the v8::Arguments structure in the arguments' space since
   // it's not controlled by GC.