crankshaft support for api method calls

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 757c58f90753242a51f988c61507f31f587a2e49..7a9cca54f5348b82f1d5599df92c548370b2a315 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -432,6 +432,26 @@ void CallDescriptors::InitializeForIsolate(Isolate* isolate) {
     descriptor->register_params_ = registers;
     descriptor->param_representations_ = representations;
   }
+  {
+    CallInterfaceDescriptor* descriptor =
+        isolate->call_descriptor(Isolate::ApiFunctionCall);
+    static Register registers[] = { rax,  // callee
+                                    rbx,  // call_data
+                                    rcx,  // holder
+                                    rdx,  // api_function_address
+                                    rsi,  // context
+    };
+    static Representation representations[] = {
+        Representation::Tagged(),    // callee
+        Representation::Tagged(),    // call_data
+        Representation::Tagged(),    // holder
+        Representation::External(),  // api_function_address
+        Representation::Tagged(),    // context
+    };
+    descriptor->register_param_count_ = 5;
+    descriptor->register_params_ = registers;
+    descriptor->param_representations_ = representations;
+  }
 }