Introduce some util code for drawing vector assets.

ui/gfx/vector_icons.h

+// Copyright (c) 2015 The Chromium Authors. All rights reserved.

[sky, 2015/07/01 16:19:52]

no (c) here and in the .cc.

[Evan Stade, 2015/07/01 21:52:59]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef UI_GFX_VECTOR_ICONS_H_
+#define UI_GFX_VECTOR_ICONS_H_
+
+#include "base/basictypes.h"
+#include "third_party/skia/include/core/SkColor.h"
+#include "ui/gfx/gfx_export.h"
+
+namespace gfx {
+
+class Canvas;
+
+enum VectorIconId {

[sky, 2015/07/01 16:19:52]

enum class, that way you can forward declare it in headers.

[Evan Stade, 2015/07/01 21:52:59]

TIL that exists. I've switched to enum class, but it doesn't let me forward
declare in image_view.h (or any header file in this CL) because there's a member
var of that type:

error: field has incomplete type 'gfx::VectorIconId'

+  VECTOR_ICON_NONE,
+
+  CHECK_CIRCLE,
+  PHOTO_CAMERA,
+};
+
+GFX_EXPORT void PaintVectorIcon(Canvas* canvas, VectorIconId id, size_t dp_size,

[sky, 2015/07/01 16:19:52]

Document what dp_size and color are.

[Evan Stade, 2015/07/01 21:52:59]

Done.

+                                SkColor color);
+
+}  // namespace gfx
+
+#endif  // UI_GFX_VECTOR_ICONS_H_