Revert of [es6] Correctify and unify ArrayBuffer and SharedArrayBuffer constructors.

src/runtime/runtime-typedarray.cc

Index: src/runtime/runtime-typedarray.cc
diff --git a/src/runtime/runtime-typedarray.cc b/src/runtime/runtime-typedarray.cc
index 14368e58c6e796cae3e100c392037cd4869ca665..753cf97f9f5f113f662ba7a4d08a35709abeedbd 100644
--- a/src/runtime/runtime-typedarray.cc
+++ b/src/runtime/runtime-typedarray.cc
@@ -12,6 +12,32 @@
 
 namespace v8 {
 namespace internal {
+
+
+RUNTIME_FUNCTION(Runtime_ArrayBufferInitialize) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 3);
+  CONVERT_ARG_HANDLE_CHECKED(JSArrayBuffer, holder, 0);
+  CONVERT_NUMBER_ARG_HANDLE_CHECKED(byteLength, 1);
+  CONVERT_BOOLEAN_ARG_CHECKED(is_shared, 2);
+  if (!holder->byte_length()->IsUndefined()) {
+    // ArrayBuffer is already initialized; probably a fuzz test.
+    return *holder;
+  }
+  size_t allocated_length = 0;
+  if (!TryNumberToSize(isolate, *byteLength, &allocated_length)) {
+    THROW_NEW_ERROR_RETURN_FAILURE(
+        isolate, NewRangeError(MessageTemplate::kInvalidArrayBufferLength));
+  }
+  if (!JSArrayBuffer::SetupAllocatingData(
+          holder, isolate, allocated_length, true,
+          is_shared ? SharedFlag::kShared : SharedFlag::kNotShared)) {
+    THROW_NEW_ERROR_RETURN_FAILURE(
+        isolate, NewRangeError(MessageTemplate::kArrayBufferAllocationFailed));
+  }
+  return *holder;
+}
+
 
 RUNTIME_FUNCTION(Runtime_ArrayBufferGetByteLength) {
   SealHandleScope shs(isolate);
@@ -41,6 +67,14 @@
   uint8_t* target_data = reinterpret_cast<uint8_t*>(target->backing_store());
   CopyBytes(target_data, source_data + start, target_length);
   return isolate->heap()->undefined_value();
+}
+
+
+RUNTIME_FUNCTION(Runtime_ArrayBufferIsView) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_CHECKED(Object, object, 0);
+  return isolate->heap()->ToBoolean(object->IsJSArrayBufferView());
 }