[Win, Linux] Always display the avatar button text at the same size.

ui/gfx/font_list.h

 // Copyright (c) 2012 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_FONT_LIST_H_
 #define UI_GFX_FONT_LIST_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 99 matching lines @@
 
   // Returns the font size in pixels.
   int GetFontSize() const;
 
   // Returns the Font vector.
   const std::vector<Font>& GetFonts() const;
 
   // Returns the first font in the list.
   const Font& GetPrimaryFont() const;
 
+  // Given a containing |height| shrinks the font size until the font list
+  // will fit within |height| while having its cap height vertically centered.
+  // Returns the correctly-sized font list.
+  //
+  // The expected layout:

[msw, 2014/08/28 21:43:50]

Perhaps the expected layout comment belongs in the function body as
implementation details, unless it has value to FontList consumers; Peter?

[Peter Kasting, 2014/08/28 21:52:03]

I think the comment should either be left here or deleted entirely.  I was never
a huge fan of adding the comment (I didn't write it originally), as things seem
clear enough to me from the paragraph above, but if they're not, the comment is
useful to callers to explain what "cap height vertically centered" means.

+  //   +--------+-----------------------------------------------+------------+
+  //   |        | y offset                                      | space      |
+  //   |        +--------+-------------------+------------------+ above      |
+  //   |        |        |                   | internal leading | cap height |
+  //   | box    | font   | ascent (baseline) +------------------+------------+
+  //   | height | height |                   | cap height                    |
+  //   |        |        |-------------------+------------------+------------+
+  //   |        |        | descent (height - baseline)          | space      |
+  //   |        +--------+--------------------------------------+ below      |
+  //   |        | space at bottom                               | cap height |
+  //   +--------+-----------------------------------------------+------------+
+  // Goal:
+  //     center of box height == center of cap height
+  //     (i.e. space above cap height == space below cap height)
+  // Restrictions:
+  //     y offset >= 0
+  //     space at bottom >= 0
+  //     (i.e. Entire font must be visible inside the box.)
+  gfx::FontList DeriveWithHeightUpperBound(int height) const;

[msw, 2014/08/28 21:43:50]

Reorder this (and the impl) with the other derive functions.

[noms (inactive), 2014/08/29 17:10:29]

Done.

+
  private:
   explicit FontList(FontListImpl* impl);
 
   static const scoped_refptr<FontListImpl>& GetDefaultImpl();
 
   scoped_refptr<FontListImpl> impl_;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_FONT_LIST_H_