For some vector icons, get the size from the vector definition.

ui/gfx/paint_vector_icon.h

 // Copyright 2015 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_GFX_PAINT_VECTOR_ICON_H_
 #define UI_GFX_PAINT_VECTOR_ICON_H_
 
 #include "base/basictypes.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/gfx/gfx_export.h"
@@ skipping 17 matching lines @@
                                       size_t dip_size,
                                       SkColor color);
 
 // As above, but also paints a badge defined by |badge_id| on top of the icon.
 // The badge uses the same canvas size and default color as the icon.
 GFX_EXPORT ImageSkia CreateVectorIconWithBadge(VectorIconId id,
                                                size_t dip_size,
                                                SkColor color,
                                                VectorIconId badge_id);
 
+// Creates a "primary UI" icon, i.e. one which is very often visible in the UI
+// and has been hand-tweaked to look good at a specific size at 1x and 2x scale
+// factors. The size is taken from the icon's canvas dimensions.
+GFX_EXPORT ImageSkia CreatePrimaryVectorIcon(VectorIconId id, SkColor color);
+
 #if defined(GFX_VECTOR_ICONS_UNSAFE) || defined(GFX_IMPLEMENTATION)
 // Takes a string of the format expected of .icon files and renders onto
 // a canvas. This should only be used as a debugging aid and should never be
 // used in production code.
 GFX_EXPORT ImageSkia CreateVectorIconFromSource(const std::string& source,
                                                 size_t dip_size,
                                                 SkColor color);
 #endif
 
 }  // namespace gfx
 
 #endif  // UI_GFX_PAINT_VECTOR_ICON_H_