Readd the clipboard service and get it compiling again.

components/mus/clipboard/clipboard_impl.h

+// Copyright 2016 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.
+
+#ifndef COMPONENTS_MUS_CLIPBOARD_CLIPBOARD_IMPL_H_
+#define COMPONENTS_MUS_CLIPBOARD_CLIPBOARD_IMPL_H_
+
+#include <stdint.h>
+
+#include <string>
+
+#include "base/macros.h"
+#include "components/mus/public/interfaces/clipboard.mojom.h"
+#include "mojo/public/cpp/bindings/binding_set.h"
+
+namespace mus {
+namespace clipboard {
+
+// Stub clipboard implementation.
+//
+// Eventually, we'll actually want to interact with the system clipboard, but
+// that's hard today because the system clipboard is asynchronous (on X11), the
+// ui::Clipboard interface is synchronous (which is what we'd use), mojo is
+// asynchronous across processes, and the WebClipboard interface is synchronous
+// (which is at least tractable).
+class ClipboardImpl : public mojom::Clipboard {
+ public:
+  // mojom::Clipboard exposes three possible clipboards.
+  static const int kNumClipboards = 3;
+
+  ClipboardImpl();
+  ~ClipboardImpl() override;
+
+  void AddBinding(mojom::ClipboardRequest request);
+
+  // mojom::Clipboard implementation.
+  void GetSequenceNumber(
+      mojom::Clipboard::Type clipboard_type,
+      const GetSequenceNumberCallback& callback) override;
+  void GetAvailableMimeTypes(
+      mojom::Clipboard::Type clipboard_types,
+      const GetAvailableMimeTypesCallback& callback) override;
+  void ReadMimeType(
+      uint64_t sequence,
+      mojom::Clipboard::Type clipboard_type,
+      const mojo::String& mime_type,
+      const ReadMimeTypeCallback& callback) override;
+  void WriteClipboardData(
+      mojom::Clipboard::Type clipboard_type,
+      mojo::Map<mojo::String, mojo::Array<uint8_t>> data,
+      const WriteClipboardDataCallback& callback) override;
+
+ private:
+  // Internal struct which stores the current state of the clipboard.
+  class ClipboardData;
+
+  // The current clipboard state. This is what is read from.
+  std::unique_ptr<ClipboardData> clipboard_state_[kNumClipboards];
+  mojo::BindingSet<mojom::Clipboard> bindings_;
+
+  DISALLOW_COPY_AND_ASSIGN(ClipboardImpl);
+};
+
+}  // namespace clipboard
+}  // namespace mus
+
+#endif  // COMPONENTS_MUS_CLIPBOARD_CLIPBOARD_IMPL_H_