[Interpreter] Add implementations of arithmetic binary op bytecodes.

src/interpreter/interpreter.h

Index: src/interpreter/interpreter.h
diff --git a/src/interpreter/interpreter.h b/src/interpreter/interpreter.h
index 64101de6570a7ecf831daa0f90f7d9cb50436796..5c332d559894b361291105f1174f3adae1200e69 100644
--- a/src/interpreter/interpreter.h
+++ b/src/interpreter/interpreter.h
@@ -9,6 +9,7 @@
 // Do not include anything from src/interpreter other than
 // src/interpreter/bytecodes.h here!
 #include "src/base/macros.h"
+#include "src/builtins.h"
 #include "src/interpreter/bytecodes.h"
 
 namespace v8 {
@@ -46,6 +47,10 @@ class Interpreter {
   BYTECODE_LIST(DECLARE_BYTECODE_HANDLER_GENERATOR)
 #undef DECLARE_BYTECODE_HANDLER_GENERATOR
 
+  // Generates code to perform the binary operations via |binop_builtin|.
+  void DoBinaryOp(Builtins::JavaScript binop_builtin,
+                  compiler::InterpreterAssembler* assembler);
+
   bool IsInterpreterTableInitialized(Handle<FixedArray> handler_table);
 
   Isolate* isolate_;