[interpreter] Add CreateFunctionContext bytecode

src/interpreter/bytecode-array-builder.h

Index: src/interpreter/bytecode-array-builder.h
diff --git a/src/interpreter/bytecode-array-builder.h b/src/interpreter/bytecode-array-builder.h
index 39e9cbf644163bd565d0e2d9d7d302aca41863fd..b0916f0d6367a094074719fef60d3fedd24e9925 100644
--- a/src/interpreter/bytecode-array-builder.h
+++ b/src/interpreter/bytecode-array-builder.h
@@ -135,6 +135,9 @@ class BytecodeArrayBuilder final : public ZoneObject {
   BytecodeArrayBuilder& CreateClosure(Handle<SharedFunctionInfo> shared_info,
                                       int flags);
 
+  // Create a new context with size |slots| in the accumulator.
+  BytecodeArrayBuilder& CreateFunctionContext(int slots);
+
   // Create a new arguments object in the accumulator.
   BytecodeArrayBuilder& CreateArguments(CreateArgumentsType type);