[ios] Removed alloc_with_zone_interceptor as unused.

ios/web/alloc_with_zone_interceptor_unittest.mm

-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#import "ios/web/alloc_with_zone_interceptor.h"
-
-#include "base/mac/scoped_nsobject.h"
-#include "testing/gtest/include/gtest/gtest.h"
-#include "testing/gtest_mac.h"
-#include "testing/platform_test.h"
-
-// Testable class to test web::AddAllocWithZoneMethod.
-@interface CRBTestAlloc : NSObject
-@end
-@implementation CRBTestAlloc
-@end
-
-namespace web {
-namespace {
-
-// Test fixture for alloc_with_zone_interceptor functions.
-typedef PlatformTest AllocWithZoneInterceptorTest;
-
-// Tests that AddAllocWithZoneMethod delegates allocation to the caller.
-TEST_F(AllocWithZoneInterceptorTest, AddAllocWithZoneMethod) {
-  NSZone* const kZone = NSDefaultMallocZone();
-  base::scoped_nsobject<CRBTestAlloc> original_result(
-      [CRBTestAlloc allocWithZone:kZone]);
-  ASSERT_TRUE([original_result isMemberOfClass:[CRBTestAlloc class]]);
-  NSString* const kResult = @"test-result";
-  AddAllocWithZoneMethod([CRBTestAlloc class], ^id(Class klass, NSZone* zone) {
-    EXPECT_EQ([CRBTestAlloc class], klass);
-    EXPECT_EQ(kZone, zone);
-    return kResult;
-  });
-  EXPECT_NSEQ(kResult, [CRBTestAlloc allocWithZone:kZone]);
-}
-
-}  // namespace
-}  // namespace web