Replace ASSERT with DCHECK in modules/fetch.

third_party/WebKit/Source/modules/fetch/DataConsumerHandleTestUtil.h

Index: third_party/WebKit/Source/modules/fetch/DataConsumerHandleTestUtil.h
diff --git a/third_party/WebKit/Source/modules/fetch/DataConsumerHandleTestUtil.h b/third_party/WebKit/Source/modules/fetch/DataConsumerHandleTestUtil.h
index 506ba6b2d2340eb14ddee1bb8c40f5d8f9437a84..a6021ba9d5b4ac412ecc4d1d14afb2da29e181ce 100644
--- a/third_party/WebKit/Source/modules/fetch/DataConsumerHandleTestUtil.h
+++ b/third_party/WebKit/Source/modules/fetch/DataConsumerHandleTestUtil.h
@@ -111,24 +111,24 @@ class DataConsumerHandleTestUtil {
 
       void RegisterThreadHolder(ThreadHolder* holder) {
         MutexLocker locker(holder_mutex_);
-        ASSERT(!holder_);
+        DCHECK(!holder_);
         holder_ = holder;
       }
       void UnregisterThreadHolder() {
         MutexLocker locker(holder_mutex_);
-        ASSERT(holder_);
+        DCHECK(holder_);
         holder_ = nullptr;
       }
       void PostTaskToReadingThread(const WebTraceLocation& location,
                                    std::unique_ptr<CrossThreadClosure> task) {
         MutexLocker locker(holder_mutex_);
-        ASSERT(holder_);
+        DCHECK(holder_);
         holder_->ReadingThread()->PostTask(location, std::move(task));
       }
       void PostTaskToUpdatingThread(const WebTraceLocation& location,
                                     std::unique_ptr<CrossThreadClosure> task) {
         MutexLocker locker(holder_mutex_);
-        ASSERT(holder_);
+        DCHECK(holder_);
         holder_->UpdatingThread()->PostTask(location, std::move(task));
       }