Remove support for externally backed elements from the API

test/cctest/compiler/test-simplified-lowering.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <limits>
 
 #include "src/compiler/access-builder.h"
 #include "src/compiler/change-lowering.h"
 #include "src/compiler/control-builders.h"
 #include "src/compiler/graph-reducer.h"
@@ skipping 240 matching lines @@
     CHECK_EQ(*src, array->get(1));
   }
 }
 
 
 TEST(RunLoadStoreArrayBuffer) {
   SimplifiedLoweringTester<Object*> t(kMachAnyTagged);
   const int index = 12;
   const int array_length = 2 * index;
   ElementAccess buffer_access =
-      AccessBuilder::ForTypedArrayElement(v8::kExternalInt8Array, true);
+      AccessBuilder::ForTypedArrayElement(kExternalInt8Array, true);
   Node* backing_store = t.LoadField(
       AccessBuilder::ForJSArrayBufferBackingStore(), t.Parameter(0));
   Node* load =
       t.LoadElement(buffer_access, backing_store, t.Int32Constant(index));
   t.StoreElement(buffer_access, backing_store, t.Int32Constant(index + 1),
                  load);
   t.Return(t.jsgraph.TrueConstant());
 
   t.LowerAllNodes();
   t.GenerateCode();
@@ skipping 1781 matching lines @@
     Bounds phi_bounds = Bounds::Either(Bounds(d.arg1), Bounds(d.arg2), z);
     NodeProperties::SetBounds(phi, phi_bounds);
 
     Node* use = t.Use(phi, d.use);
     t.Return(use);
     t.Lower();
 
     CHECK_EQ(d.expected, OpParameter<MachineType>(phi));
   }
 }