Add 1px black border for ChromeOS status button.

gfx/canvas_skia.h

Index: gfx/canvas_skia.h
diff --git a/gfx/canvas_skia.h b/gfx/canvas_skia.h
index 27781ff24f2633651f53a58e6da152fef11dcebc..d30978428f941c764d05579696346f0eec38cac0 100644
--- a/gfx/canvas_skia.h
+++ b/gfx/canvas_skia.h
@@ -67,11 +67,13 @@ class CanvasSkia : public skia::PlatformCanvas,
   void DrawGdkPixbuf(GdkPixbuf* pixbuf, int x, int y);
 #endif
 
-#ifdef OS_WIN  // Only implemented on Windows for now.
-  // Draws text with a 1-pixel halo around it of the given color. It allows
-  // ClearType to be drawn to an otherwise transparenct bitmap for drag images.
-  // Drag images have only 1-bit of transparency, so we don't do any fancy
-  // blurring.
+#if defined(OS_WIN) || (defined(OS_POSIX) && !defined(OS_MACOSX))
+  // Draws text with a 1-pixel halo around it of the given color.
+  // On Windows, it allows ClearType to be drawn to an otherwise transparenct
+  //   bitmap for drag images. Drag images have only 1-bit of transparency, so
+  //   we don't do any fancy blurring.
+  // On Linux, text with halo is created by stroking it with 2px |halo_color|
+  //   then filling it with |text_color|.
   void DrawStringWithHalo(const std::wstring& text,
                           const gfx::Font& font,
                           const SkColor& text_color,