src: re-enable fast math on arm

Ref: #1376
Ref: #1398
Issue fixed in V8: https://chromium.googlesource.com/v8/v8/+/81703350bbb9923d211fe5b79e90bd458b0916e2
V8-Bug: https://code.google.com/p/v8/issues/detail?id=4019

PR-URL: #2592
Reviewed-By: Rod Vagg <rod@vagg.org>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>

Author: targos

src/node.cc

@@ -3603,20 +3603,6 @@ void Init(int* argc,
                 DispatchDebugMessagesAsyncCallback);
   uv_unref(reinterpret_cast<uv_handle_t*>(&dispatch_debug_messages_async));
 
-#if defined(__ARM_ARCH_6__) || \
-    defined(__ARM_ARCH_6J__) || \
-    defined(__ARM_ARCH_6K__) || \
-    defined(__ARM_ARCH_6M__) || \
-    defined(__ARM_ARCH_6T2__) || \
-    defined(__ARM_ARCH_6ZK__) || \
-    defined(__ARM_ARCH_6Z__)
-  // See https://github.com/nodejs/node/issues/1376
-  // and https://code.google.com/p/v8/issues/detail?id=4019
-  // TODO(bnoordhuis): Remove test/parallel/test-arm-math-exp-regress-1376.js
-  // and this workaround when v8:4019 has been fixed and the patch back-ported.
-  V8::SetFlagsFromString("--nofast_math", sizeof("--nofast_math") - 1);
-#endif
-
 #if defined(NODE_V8_OPTIONS)
   // Should come before the call to V8::SetFlagsFromCommandLine()
   // so the user can disable a flag --foo at run-time by passing