Allow various font weights in gfx.

ui/gfx/font.cc

Index: ui/gfx/font.cc
diff --git a/ui/gfx/font.cc b/ui/gfx/font.cc
index 60a7acd424f5f12193b30dd2e62ad5440269c0d2..ac7b7491a6cdcb98caa8e889900db693f454d9f6 100644
--- a/ui/gfx/font.cc
+++ b/ui/gfx/font.cc
@@ -41,8 +41,8 @@ Font::Font(const std::string& font_name, int font_size)
 Font::~Font() {
 }
 
-Font Font::Derive(int size_delta, int style) const {
-  return platform_font_->DeriveFont(size_delta, style);
+Font Font::Derive(int size_delta, int style, Font::Weight weight) const {
+  return platform_font_->DeriveFont(size_delta, style, weight);
 }
 
 int Font::GetHeight() const {
@@ -77,6 +77,10 @@ int Font::GetFontSize() const {
   return platform_font_->GetFontSize();
 }
 
+Font::Weight Font::GetWeight() const {
+  return platform_font_->GetWeight();
+}
+
 const FontRenderParams& Font::GetFontRenderParams() const {
   return platform_font_->GetFontRenderParams();
 }
@@ -87,4 +91,10 @@ NativeFont Font::GetNativeFont() const {
 }
 #endif
 
+#ifndef NDEBUG
+std::ostream& operator<<(std::ostream& stream, const Font::Weight weight) {
+  return stream << static_cast<int>(weight);
+}
+#endif
+
 }  // namespace gfx