Add FakeDisplayDelegate for off device usage.

ui/display/fake_display_snapshot.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 UI_DISPLAY_FAKE_DISPLAY_SNAPSHOT_H_
+#define UI_DISPLAY_FAKE_DISPLAY_SNAPSHOT_H_
+
+#include <stdint.h>
+
+#include <memory>
+#include <string>
+
+#include "base/macros.h"
+#include "ui/display/display_export.h"
+#include "ui/display/types/display_mode.h"
+#include "ui/display/types/display_snapshot.h"
+#include "ui/gfx/geometry/size.h"
+
+namespace display {
+
+// A display snapshot that doesn't correspond to a physical display, used when
+// running off device.
+class FakeDisplaySnapshot : public ui::DisplaySnapshot {
+ public:
+  FakeDisplaySnapshot(int64_t display_id,
+                      const gfx::Size& display_size,
+                      ui::DisplayConnectionType type);
+  ~FakeDisplaySnapshot() override;
+
+  // DisplaySnapshot:
+  std::string ToString() const override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(FakeDisplaySnapshot);
+};
+
+}  // namespace display
+
+#endif  // UI_DISPLAY_FAKE_DISPLAY_SNAPSHOT_H_