[Interpreter] Add support for JS calls.

src/interpreter/bytecode-array-builder.cc

Index: src/interpreter/bytecode-array-builder.cc
diff --git a/src/interpreter/bytecode-array-builder.cc b/src/interpreter/bytecode-array-builder.cc
index dba816d61810d63259412f946f219494c2e134ef..ff3b4883554d114035d6b8f33a2601358cea3f06 100644
--- a/src/interpreter/bytecode-array-builder.cc
+++ b/src/interpreter/bytecode-array-builder.cc
@@ -182,6 +182,18 @@ BytecodeArrayBuilder& BytecodeArrayBuilder::Return() {
 }
 
 
+BytecodeArrayBuilder& BytecodeArrayBuilder::CallJS(Register first_arg,
+                                                   size_t arg_count) {
+  if (FitsInByteOperand(arg_count)) {
+    Output(Bytecode::kCallJS, first_arg.ToOperand(),
+           static_cast<uint8_t>(arg_count));
+  } else {
+    UNIMPLEMENTED();
+  }
+  return *this;
+}
+
+
 size_t BytecodeArrayBuilder::GetConstantPoolEntry(Handle<Object> object) {
   // These constants shouldn't be added to the constant pool, the should use
   // specialzed bytecodes instead.
@@ -225,6 +237,7 @@ bool BytecodeArrayBuilder::OperandIsValid(Bytecode bytecode, int operand_index,
   switch (operand_type) {
     case OperandType::kNone:
       return false;
+    case OperandType::kCount:
     case OperandType::kImm8:
     case OperandType::kIdx:
       return true;