[wasm] Introduce the TrapIf and TrapUnless operators to generate trap code.

src/wasm/wasm-external-refs.cc

Index: src/wasm/wasm-external-refs.cc
diff --git a/src/wasm/wasm-external-refs.cc b/src/wasm/wasm-external-refs.cc
index 4c4c91b29cada9dd7c1ca0a1226d966f5b253952..e982cc7f99bfe8c59c3e6d19aad021645e175e2b 100644
--- a/src/wasm/wasm-external-refs.cc
+++ b/src/wasm/wasm-external-refs.cc
@@ -208,6 +208,19 @@ void float64_pow_wrapper(double* param0, double* param1) {
   double y = ReadDoubleValue(param1);
   WriteDoubleValue(param0, Pow(x, y));
 }
+
+static WasmTrapCallbackForTesting wasm_trap_callback_for_testing = nullptr;
+
+void set_trap_callback_for_testing(WasmTrapCallbackForTesting callback) {
+  wasm_trap_callback_for_testing = callback;
+}
+
+void call_trap_callback_for_testing() {
+  if (wasm_trap_callback_for_testing) {
+    wasm_trap_callback_for_testing();
+  }
+}
+
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8