Revert of Restore per-TypedArray-class length accessors as a perf workaround...

Revert of Restore per-TypedArray-class length accessors as a perf workaround (patchset #2 id:20001 of https://codereview.chromium.org/1624383003/ )

Reason for revert:
This patch actually seemed to cause a further GameBoy regression! Reverting it seems to address the regression.

Original issue's description:
> Restore per-TypedArray-class length accessors as a perf workaround
>
> This patch is a workaround to the performance regression caused by
> implementing the ES2015 TypedArray prototype chain: Include a
> per-TypedArray-subclass length getter so that the superclass getter does
> not become polymorphic. The patch appears to fix a regression in the
> Gameboy Octane benchmark.
>
> BUG=chromium:579905
> R=adamk
> LOG=Y
>
> Committed: https://crrev.com/03ce7711e474a0ef74f723b30ae1527c89dec010
> Cr-Commit-Position: refs/heads/master@{#33501}

R=adamk@chromium.org
BUG=chromium:579905,chromium:593634
LOG=Y

Review URL: https://codereview.chromium.org/1812143004

Cr-Commit-Position: refs/heads/master@{#34906}

src/js/typedarray.js

@@ -281,14 +281,6 @@ function NAMEConstructor(arg1, arg2, arg3) {
   }
 }
 
-// TODO(littledan): Remove this performance workaround BUG(chromium:579905)
-function NAME_GetLength() {
-  if (!(%_ClassOf(this) === 'NAME')) {
-    throw MakeTypeError(kIncompatibleMethodReceiver, "NAME.length", this);
-  }
-  return %_TypedArrayGetLength(this);
-}
-
 function NAMESubArray(begin, end) {
   var beginInt = TO_INTEGER(begin);
   if (!IS_UNDEFINED(end)) {
@@ -888,9 +880,6 @@ macro SETUP_TYPED_ARRAY(ARRAY_ID, NAME, ELEMENT_SIZE)
   %AddNamedProperty(GlobalNAME.prototype,
                     "BYTES_PER_ELEMENT", ELEMENT_SIZE,
                     READ_ONLY | DONT_ENUM | DONT_DELETE);
-  // TODO(littledan): Remove this performance workaround BUG(chromium:579905)
-  utils.InstallGetter(GlobalNAME.prototype, "length", NAME_GetLength,
-                      DONT_ENUM | DONT_DELETE);
 endmacro
 
 TYPED_ARRAYS(SETUP_TYPED_ARRAY)

test/mjsunit/es6/typedarray-proto.js

@@ -28,17 +28,13 @@ assertEquals(TypedArrayPrototype.__proto__, Object.prototype);
 let classProperties = new Set([
   "length", "name", "arguments", "caller", "prototype", "BYTES_PER_ELEMENT"
 ]);
-let instanceProperties = new Set([
-  "BYTES_PER_ELEMENT", "constructor", "prototype",
-  // length is also an instance property as a temporary workaround to
-  // BUG(chromium:579905). TODO(littledan): remove the workaround
-  "length"
-]);
+let instanceProperties = new Set(["BYTES_PER_ELEMENT", "constructor", "prototype"]);
 
 function functionProperties(object) {
   return Object.getOwnPropertyNames(object).filter(function(name) {
     return typeof Object.getOwnPropertyDescriptor(object, name).value
-        == "function" && name != 'constructor';
+        == "function"
+      && name != 'constructor' && name != 'subarray';
   });
 }