[wasm] asm.js: Add asm_wasm variant to test asm.js->wasm pipeline.

test/unittests/unittests.status

 # Copyright 2014 the V8 project authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 [
 ['byteorder == big', {
   # TODO(mips-team): Fix Wasm for big-endian.
   'WasmModuleVerifyTest*': [SKIP],
   'WasmFunctionVerifyTest*': [SKIP],
   'WasmDecoderTest.TableSwitch*': [SKIP],
   'WasmDecoderTest.AllLoadMemCombinations': [SKIP],
   'AstDecoderTest.AllLoadMemCombinations': [SKIP],
   'AstDecoderTest.AllStoreMemCombinations': [SKIP],
 }],  # 'byteorder == big'
 ['arch == x87', {
   'Ieee754.Expm1': [SKIP],
   'Ieee754.Cos': [SKIP],
   'Ieee754.Tan': [SKIP],
   'Ieee754.Acosh': [SKIP],
   'Ieee754.Asinh': [SKIP],
 }],  # 'arch == x87'
+
+['variant == asm_wasm', {
+  '*': [SKIP],
+}],  # variant == asm_wasm
+
 ]