Reland "ARM64: Add NEON support"

DEPS

 # Note: The buildbots evaluate this file with CWD set to the parent
 # directory and assume that the root of the checkout is in ./v8/, so
 # all paths in here must match this assumption.
 
 vars = {
   "chromium_url": "https://chromium.googlesource.com",
 }
 
 deps = {
   "v8/build":
@@ skipping 19 matching lines @@
   "v8/testing/gmock":
     Var("chromium_url") + "/external/googlemock.git" + "@" + "0421b6f358139f02e102c9c332ce19a33faf75be",
   "v8/test/benchmarks/data":
     Var("chromium_url") + "/v8/deps/third_party/benchmarks.git" + "@" + "05d7188267b4560491ff9155c5ee13e207ecd65f",
   "v8/test/mozilla/data":
     Var("chromium_url") + "/v8/deps/third_party/mozilla-tests.git" + "@" + "f6c578a10ea707b1a8ab0b88943fe5115ce2b9be",
   "v8/test/test262/data":
     Var("chromium_url") + "/external/github.com/tc39/test262.git" + "@" + "230f9fc5688ce76bfaa99aba5f680a159eaac9e2",
   "v8/test/test262/harness":
     Var("chromium_url") + "/external/github.com/test262-utils/test262-harness-py.git" + "@" + "0f2acdd882c84cff43b9d60df7574a1901e2cdcd",
+  "v8/test/cctest/traces-arm64":
+    Var("chromium_url") + "/external/git.linaro.org/arm/vixl-simulator-traces.git" + "@" + "6168e7e1eec52c9cb0a62f87f94df0582dc48aa8",
   "v8/tools/clang":
     Var("chromium_url") + "/chromium/src/tools/clang.git" + "@" + "49df471350a60efaec6951f321dd65475496ba17",
   "v8/test/wasm-js":
     Var("chromium_url") + "/external/github.com/WebAssembly/spec.git" + "@" + "07fd6430f879d36928d179a62d9bdeed82286065",
 }
 
 deps_os = {
   "android": {
     "v8/third_party/android_tools":
       Var("chromium_url") + "/android_tools.git" + "@" + "b65c4776dac2cf1b80e969b3b2d4e081b9c84f29",
@@ skipping 236 matching lines @@
     'name': 'clang',
     'pattern': '.',
     'action': ['python', 'v8/tools/clang/scripts/update.py', '--if-needed'],
   },
   {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     "pattern": ".",
     "action": ["python", "v8/gypfiles/gyp_v8", "--running-as-hook"],
   },
 ]