[wasm][asm.js] Adding custom asm.js lexer.

BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/dcheck_always_on.gni")
 import("//build/config/mips.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 
@@ skipping 900 matching lines @@
     "src/api-arguments.cc",
     "src/api-arguments.h",
     "src/api-natives.cc",
     "src/api-natives.h",
     "src/api.cc",
     "src/api.h",
     "src/arguments.cc",
     "src/arguments.h",
     "src/asmjs/asm-js.cc",
     "src/asmjs/asm-js.h",
+    "src/asmjs/asm-names.h",
+    "src/asmjs/asm-scanner.cc",
+    "src/asmjs/asm-scanner.h",
     "src/asmjs/asm-typer.cc",
     "src/asmjs/asm-typer.h",
     "src/asmjs/asm-types.cc",
     "src/asmjs/asm-types.h",
     "src/asmjs/asm-wasm-builder.cc",
     "src/asmjs/asm-wasm-builder.h",
     "src/asmjs/switch-logic.cc",
     "src/asmjs/switch-logic.h",
     "src/assembler-inl.h",
     "src/assembler.cc",
@@ skipping 2203 matching lines @@
   ]
 
   configs = [
     ":external_config",
     ":internal_config_base",
   ]
 }
 
 v8_fuzzer("wasm_compile_fuzzer") {
 }