[ios] Removed DCHECK which prevents WKProcessPool manual creation.

ios/web/web_state/ui/wk_web_view_configuration_provider.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/web_state/ui/wk_web_view_configuration_provider.h"
 
 #import <Foundation/Foundation.h>
-#import <objc/runtime.h>
 #import <WebKit/WebKit.h>
 
 #include "base/ios/ios_util.h"
 #import "base/ios/weak_nsobject.h"
 #import "base/logging.h"
-#import "ios/web/alloc_with_zone_interceptor.h"
 #include "ios/web/public/browser_state.h"
 #import "ios/web/web_state/js/page_script_util.h"
 #import "ios/web/web_state/ui/crw_wk_script_message_router.h"
-#import "ios/web/web_state/web_view_internal_creation_util.h"
-
-#if !defined(NDEBUG)
-
-namespace {
-BOOL gAllowWKProcessPoolCreation = NO;
-
-// By default WKProcessPool creation is not allowed by embedder to prevent
-// issues with browsing data clearing. However some iOS system methods do create
-// WKProcessPool inside, which is perfectly fine and should be allowed. This
-// method whitelists given |klass| with given |selector|, so creation of
-// WKProcessPool is allowed inside that selector call. This function currently
-// supports Objective-C methods with up to 4 arguments and needs to be updated
-// if support for more arguments is required.
-void AllowWKProcessPoolCreation(Class klass, SEL selector) {
-  Method method = class_getInstanceMethod(klass, selector);
-  IMP originalImp = method_getImplementation(method);
-  IMP safeImp = imp_implementationWithBlock(
-      ^(id self, id arg1, id arg2, id arg3, id arg4) {
-        BOOL oldAllowWKProcessPoolCreation = gAllowWKProcessPoolCreation;
-        gAllowWKProcessPoolCreation = YES;
-        id result = originalImp(self, selector, arg1, arg2, arg3, arg4);
-        gAllowWKProcessPoolCreation = oldAllowWKProcessPoolCreation;
-        return result;
-      });
-
-  method_setImplementation(method, safeImp);
-}
-}
-
-@interface WKProcessPool (CRWAdditions)
-@end
-
-@implementation WKProcessPool (CRWAdditions)
-
-+ (void)load {
-  id (^allocator)(Class klass, NSZone* zone) = ^id(Class klass, NSZone* zone) {
-    if (gAllowWKProcessPoolCreation || web::IsWebViewAllocInitAllowed()) {
-      return NSAllocateObject(klass, 0, zone);
-    }
-    // You have hit this because you are trying to create a WKProcessPool
-    // directly or indirectly (f.e. by creating WKWebViewConfiguration
-    // manually). Please use GetWebViewConfiguration() to get
-    // WKWebViewConfiguration object.
-    NOTREACHED();
-    return nil;
-  };
-  web::AddAllocWithZoneMethod([WKProcessPool class], allocator);
-
-  if (!base::ios::IsRunningOnIOS9OrLater())
-    return;
-
-  // Make sure that WKWebsiteDataStore is allowed to create WKProcessPool for
-  // internal implementation purposes.
-  AllowWKProcessPoolCreation(
-      [WKWebsiteDataStore class],
-      @selector(fetchDataRecordsOfTypes:completionHandler:completionHandler:));
-  AllowWKProcessPoolCreation(
-      [WKWebsiteDataStore class],
-      @selector(removeDataOfTypes:forDataRecords:completionHandler:));
-  AllowWKProcessPoolCreation(
-      [WKWebsiteDataStore class],
-      @selector(removeDataOfTypes:modifiedSince:completionHandler:));
-}
-
-@end
-
-#endif  // !defined(NDEBUG)
 
 namespace web {
 
 namespace {
 // A key used to associate a WKWebViewConfigurationProvider with a BrowserState.
 const char kWKWebViewConfigProviderKeyName[] = "wk_web_view_config_provider";
 
 // Returns an autoreleased instance of WKUserScript to be added to
 // configuration's userContentController.
 WKUserScript* GetEarlyPageScript() {
@@ skipping 33 matching lines @@
   if (!configuration_) {
     configuration_.reset([[WKWebViewConfiguration alloc] init]);
     if (is_off_the_record_ && base::ios::IsRunningOnIOS9OrLater()) {
       // WKWebsiteDataStore is iOS9 only.
       [configuration_
           setWebsiteDataStore:[WKWebsiteDataStore nonPersistentDataStore]];
     }
     // setJavaScriptCanOpenWindowsAutomatically is required to support popups.
     [[configuration_ preferences] setJavaScriptCanOpenWindowsAutomatically:YES];
     [[configuration_ userContentController] addUserScript:GetEarlyPageScript()];
-#if !defined(NDEBUG)
-    // Lazily load WKProcessPool. -[[WKProcessPool alloc] init] call is not
-    // allowed except when creating config object inside this class.
-    // Unmanaged creation of WKProcessPool may lead to issues with cookie
-    // clearing and Browsing Data Partitioning implementation.
-    gAllowWKProcessPoolCreation = YES;
-    CHECK([configuration_ processPool]);
-    gAllowWKProcessPoolCreation = NO;
-#endif  // !defined(NDEBUG)
   }
   // Prevent callers from changing the internals of configuration.
   return [[configuration_ copy] autorelease];
 }
 
 CRWWKScriptMessageRouter*
 WKWebViewConfigurationProvider::GetScriptMessageRouter() {
   DCHECK([NSThread isMainThread]);
   if (!router_) {
     WKUserContentController* userContentController =
@@ skipping 14 matching lines @@
   configuration_.reset();
   router_.reset();
   // Make sure that no one retains configuration, router, processPool.
   DCHECK(!weak_configuration);
   DCHECK(!weak_router);
   // TODO(crbug.com/522672): Enable this DCHECK.
   // DCHECK(!weak_process_pool);
 }
 
 }  // namespace web