Implement debugName() in WebDataConsumerHandle subclasses in Blink

Source/modules/fetch/DataConsumerHandleUtil.cpp

Index: Source/modules/fetch/DataConsumerHandleUtil.cpp
diff --git a/Source/modules/fetch/DataConsumerHandleUtil.cpp b/Source/modules/fetch/DataConsumerHandleUtil.cpp
index 587b92628168468b8e970e4809d1ed2ade7d8d63..e6d9e2491e8e83ddc8d756d1fea8744521947e64 100644
--- a/Source/modules/fetch/DataConsumerHandleUtil.cpp
+++ b/Source/modules/fetch/DataConsumerHandleUtil.cpp
@@ -39,6 +39,8 @@ private:
         }
     };
     Reader* obtainReaderInternal(Client*) override { return new ReaderImpl; }
+
+    const char* debugName() const override { return "WaitingHandle"; }
 };
 
 class RepeatingReader final : public WebDataConsumerHandle::Reader {
@@ -69,11 +71,13 @@ private:
 class DoneHandle final : public WebDataConsumerHandle {
 private:
     Reader* obtainReaderInternal(Client* client) override { return new RepeatingReader(Done, client); }
+    const char* debugName() const override { return "DoneHandle"; }
 };
 
 class UnexpectedErrorHandle final : public WebDataConsumerHandle {
 private:
     Reader* obtainReaderInternal(Client* client) override { return new RepeatingReader(UnexpectedError, client); }
+    const char* debugName() const override { return "UnexpectedErrorHandle"; }
 };
 
 class WebToFetchDataConsumerHandleAdapter : public FetchDataConsumerHandle {
@@ -102,6 +106,8 @@ private:
 
     Reader* obtainReaderInternal(Client* client) override { return new ReaderImpl(m_handle->obtainReader(client)); }
 
+    const char* debugName() const override { return m_handle->debugName(); }
+
     OwnPtr<WebDataConsumerHandle> m_handle;
 };