Add SIMD.Float32x4 functions.

src/heap-snapshot-generator.cc

Index: src/heap-snapshot-generator.cc
diff --git a/src/heap-snapshot-generator.cc b/src/heap-snapshot-generator.cc
index a27f4194587f0f8705c4ee2f938f2b92d07feef4..a63caf0c29493fbc7380e52f4b81dd43b6f8e80d 100644
--- a/src/heap-snapshot-generator.cc
+++ b/src/heap-snapshot-generator.cc
@@ -149,12 +149,13 @@ const char* HeapEntry::TypeAsString() {
     case kArray: return "/array/";
     case kRegExp: return "/regexp/";
     case kHeapNumber: return "/number/";
+    case kSimdValue:
+      return "/simd/";
     case kNative: return "/native/";
     case kSynthetic: return "/synthetic/";
     case kConsString: return "/concatenated string/";
     case kSlicedString: return "/sliced string/";
     case kSymbol: return "/symbol/";
-    case kSimdValue: return "/simd/";
     default: return "???";
   }
 }