Add missing 'SharedArrayBuffer' feature tag

test/built-ins/ArrayBuffer/prototype/byteLength/this-is-sharedarraybuffer.js

@@ -4,6 +4,7 @@
 /*---
 esid: sec-get-arraybuffer.prototype.bytelength
 description: Throws a TypeError exception when `this` is a SharedArrayBuffer
+features: [SharedArrayBuffer]
 ---*/
 
 var getter = Object.getOwnPropertyDescriptor(

test/built-ins/ArrayBuffer/prototype/slice/this-is-sharedarraybuffer.js

@@ -5,6 +5,7 @@
 esid: sec-arraybuffer.prototype.slice
 description: >
   Throws a TypeError if `this` is a SharedArrayBuffer
+features: [SharedArrayBuffer]
 ---*/
 
 assert.throws(TypeError, function() {

test/built-ins/TypedArrays/internals/Get/indexed-value-sab.js

@@ -6,7 +6,7 @@ esid: sec-integer-indexed-exotic-objects-get-p-receiver
 description: >
   Return value from valid numeric index, with SharedArrayBuffer
 includes: [testTypedArray.js]
-features: [TypedArray]
+features: [TypedArray, SharedArrayBuffer]
 ---*/
 
 var proto = TypedArray.prototype;