fix: implement ses.getBlobData() for NetworkService (#20041)

* pass data pipe to JS

* implement reading buffer

* re-enable ses.getBlobData test

* remove AtomBlobReader

shell/browser/api/atom_api_data_pipe_holder.h

@@ -0,0 +1,53 @@
+// Copyright (c) 2019 GitHub, Inc.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+#ifndef SHELL_BROWSER_API_ATOM_API_DATA_PIPE_HOLDER_H_
+#define SHELL_BROWSER_API_ATOM_API_DATA_PIPE_HOLDER_H_
+
+#include <string>
+
+#include "gin/handle.h"
+#include "gin/wrappable.h"
+#include "services/network/public/cpp/data_element.h"
+#include "services/network/public/mojom/data_pipe_getter.mojom.h"
+
+namespace electron {
+
+namespace api {
+
+// Retains reference to the data pipe.
+class DataPipeHolder : public gin::Wrappable<DataPipeHolder> {
+ public:
+  static gin::WrapperInfo kWrapperInfo;
+
+  static gin::Handle<DataPipeHolder> Create(
+      v8::Isolate* isolate,
+      const network::DataElement& element);
+  static gin::Handle<DataPipeHolder> From(v8::Isolate* isolate,
+                                          const std::string& id);
+
+  // Read all data at once.
+  //
+  // TODO(zcbenz): This is apparently not suitable for really large data, but
+  // no one has complained about it yet.
+  v8::Local<v8::Promise> ReadAll(v8::Isolate* isolate);
+
+  // The unique ID that can be used to receive the object.
+  const std::string& id() const { return id_; }
+
+ private:
+  explicit DataPipeHolder(const network::DataElement& element);
+  ~DataPipeHolder() override;
+
+  std::string id_;
+  network::mojom::DataPipeGetterPtr data_pipe_;
+
+  DISALLOW_COPY_AND_ASSIGN(DataPipeHolder);
+};
+
+}  // namespace api
+
+}  // namespace electron
+
+#endif  // SHELL_BROWSER_API_ATOM_API_DATA_PIPE_HOLDER_H_