Add FakeDisplayDelegate for off device usage.

ui/display/fake_display_snapshot.cc

Index: ui/display/fake_display_snapshot.cc
diff --git a/ui/display/fake_display_snapshot.cc b/ui/display/fake_display_snapshot.cc
new file mode 100644
index 0000000000000000000000000000000000000000..cf6f44c6729f32d42476f1bc1c18da8d7106717c
--- /dev/null
+++ b/ui/display/fake_display_snapshot.cc
@@ -0,0 +1,52 @@
+// 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.
+
+#include "ui/display/fake_display_snapshot.h"
+
+#include <vector>
+
+#include "base/strings/stringprintf.h"
+
+namespace display {
+
+namespace {
+
+// For a non high-DPI display (96 dpi) use a pitch of 265µm.
+static const float kDisplayPitchMM = 0.265;
+
+}  // namespace
+
+FakeDisplaySnapshot::FakeDisplaySnapshot(int64_t display_id,
+                                         const gfx::Size& display_size,
+                                         ui::DisplayConnectionType type)
+    : DisplaySnapshot(display_id,
+                      gfx::Point(0, 0),
+                      gfx::Size(display_size.width() * kDisplayPitchMM,
+                                display_size.height() * kDisplayPitchMM),
+                      type,
+                      false,
+                      false,
+                      false,
+                      "Fake Display",

[rjkroege, 2016/09/15 00:52:46]

given that there could be more than one, can you give each display a different
name?

[kylechar, 2016/09/15 17:31:55]

Done.

+                      base::FilePath(),
+                      std::vector<std::unique_ptr<const ui::DisplayMode>>(),
+                      std::vector<uint8_t>(),
+                      nullptr,
+                      nullptr) {
+  ui::DisplayMode mode(display_size, false, 60.0f);
+  modes_.push_back(mode.Clone());
+
+  native_mode_ = modes_.front().get();
+}
+
+FakeDisplaySnapshot::~FakeDisplaySnapshot() {}
+
+std::string FakeDisplaySnapshot::ToString() const {
+  return base::StringPrintf(
+      "id=%ld current_mode=%s physical_size=%s", display_id_,
+      current_mode_ ? current_mode_->ToString().c_str() : "nullptr",
+      physical_size_.ToString().c_str());
+}
+
+}  // namespace display