Add palette tool/manager.

ash/common/system/chromeos/palette/palette_ids.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 ASH_COMMON_SYSTEM_CHROMEOS_PALETTE_PALETTE_IDS_H_
+#define ASH_COMMON_SYSTEM_CHROMEOS_PALETTE_PALETTE_IDS_H_
+
+#include <string>
+
+#include "ash/ash_export.h"
+
+namespace ash {
+
+enum class PaletteGroup { ACTION, MODE };
+
+enum class PaletteToolId {
+  NONE,
+  CREATE_NEW_NOTE,
+  SCREENSHOT,
+  CAPTURE_REGION,
+  PRESENTATION,
+  MAGNIFY,
+};
+
+// Helper functions that convert PaletteToolIds and PaletteGroups to strings.
+ASH_EXPORT std::string PaletteToolIdToString(PaletteToolId tool_id);

[Evan Stade, 2016/07/13 18:31:12]

Are these just for debug?

[jdufault, 2016/07/13 19:22:39]

Essentially, though right now the palette tool stubs are using
PaletteToolIdToString for display strings - eventually though those will be
properly i18nized.

+ASH_EXPORT std::string PaletteGroupToString(PaletteGroup group);
+
+}  // namespace ash
+
+#endif  // ASH_COMMON_SYSTEM_CHROMEOS_PALETTE_PALETTE_IDS_H_