Introduce FetchFormDataConsumerHandle.

Source/modules/fetch/FetchBlobDataConsumerHandleTest.cpp

Index: Source/modules/fetch/FetchBlobDataConsumerHandleTest.cpp
diff --git a/Source/modules/fetch/FetchBlobDataConsumerHandleTest.cpp b/Source/modules/fetch/FetchBlobDataConsumerHandleTest.cpp
index 83ac968f6b004d2a2d6c0010a32e6e8e86a8b2fb..c0f1a92fef9d8da3db56c068f9dfe6ec786b128a 100644
--- a/Source/modules/fetch/FetchBlobDataConsumerHandleTest.cpp
+++ b/Source/modules/fetch/FetchBlobDataConsumerHandleTest.cpp
@@ -341,5 +341,41 @@ TEST_F(FetchBlobDataConsumerHandleTest, BodyLoadErrorTest)
     EXPECT_EQ(kUnexpectedError, r->result());
 }
 
+TEST_F(FetchBlobDataConsumerHandleTest, drainAsBlobDataHandle)
+{
+    auto factory = new StrictMock<MockLoaderFactory>;
+
+    RefPtr<BlobDataHandle> blobDataHandle = createBlobDataHandle("Once upon a time");
+    OwnPtr<FetchDataConsumerHandle> handle
+        = FetchBlobDataConsumerHandle::create(&document(), blobDataHandle, factory);
+
+    size_t size = 0;
+    EXPECT_EQ(blobDataHandle, handle->obtainReader(nullptr)->drainAsBlobDataHandle());
+    EXPECT_FALSE(handle->obtainReader(nullptr)->drainAsFormData());
+
+    EXPECT_EQ(kDone, handle->obtainReader(nullptr)->read(nullptr, 0, kNone, &size));
+}
+
+TEST_F(FetchBlobDataConsumerHandleTest, drainAsFormData)
+{
+    auto factory = new StrictMock<MockLoaderFactory>;
+
+    RefPtr<BlobDataHandle> blobDataHandle = createBlobDataHandle("Once upon a time");
+    OwnPtr<FetchDataConsumerHandle> handle
+        = FetchBlobDataConsumerHandle::create(&document(), blobDataHandle, factory);
+
+    RefPtr<FormData> formData = handle->obtainReader(nullptr)->drainAsFormData();
+    ASSERT_TRUE(formData);
+    EXPECT_TRUE(formData->hasOneRef());
+    ASSERT_EQ(1u, formData->elements().size());
+    EXPECT_EQ(FormDataElement::encodedBlob, formData->elements()[0].m_type);
+    EXPECT_EQ(blobDataHandle->uuid(), formData->elements()[0].m_blobUUID);
+    EXPECT_EQ(blobDataHandle, formData->elements()[0].m_optionalBlobDataHandle);
+
+    EXPECT_FALSE(handle->obtainReader(nullptr)->drainAsBlobDataHandle());
+    size_t size;
+    EXPECT_EQ(kDone, handle->obtainReader(nullptr)->read(nullptr, 0, kNone, &size));
+}
+
 } // namespace
 } // namespace blink