Expose SIMD.Float32x4 type to Javascript.

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 f1bdc71cca03dc3cf1d0277d65a5f2997595f495..04b3d26e97826a226124f4c1df6acf42bd3bff86 100644
--- a/src/heap-snapshot-generator.cc
+++ b/src/heap-snapshot-generator.cc
@@ -149,12 +149,12 @@ 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 "???";
   }
 }