[runtime] Unify and fix the strict equality comparison.

src/runtime.js

Index: src/runtime.js
diff --git a/src/runtime.js b/src/runtime.js
index 5683f8422c372cc39241a77711b26d3bef02e166..4de9c2997df1a5debf4341aaef8fdb6d212b2902 100644
--- a/src/runtime.js
+++ b/src/runtime.js
@@ -127,6 +127,7 @@ EQUALS = function EQUALS(y) {
     } else if (IS_NULL_OR_UNDEFINED(x)) {
       return IS_NULL_OR_UNDEFINED(y) ? 0 : 1;
     } else if (IS_SIMD_VALUE(x)) {
+      if (!IS_SIMD_VALUE(y)) return 1;  // not equal
        return %SimdEquals(x, y);
     } else {
       // x is an object.
@@ -142,26 +143,6 @@ EQUALS = function EQUALS(y) {
   }
 }
 
-// ECMA-262, section 11.9.4, page 56.
-STRICT_EQUALS = function STRICT_EQUALS(x) {
-  if (IS_STRING(this)) {
-    if (!IS_STRING(x)) return 1;  // not equal
-    return %StringEquals(this, x);
-  }
-
-  if (IS_NUMBER(this)) {
-    if (!IS_NUMBER(x)) return 1;  // not equal
-    return %NumberEquals(this, x);
-  }
-
-  if (IS_SIMD_VALUE(this)) return %SimdEquals(this, x);
-
-  // If anything else gets here, we just do simple identity check.
-  // Objects (including functions), null, undefined and booleans were
-  // checked in the CompareStub, so there should be nothing left.
-  return %_ObjectEquals(this, x) ? 0 : 1;
-}
-
 
 // ECMA-262, section 11.8.5, page 53. The 'ncr' parameter is used as
 // the result when either (or both) the operands are NaN.