Re-add GetStringWidth to PlatformFont, and use that from Font

Font is supposed to be an abstraction, so shouldn't depend directly on Skia. Partially reverses
http://codereview.chromium.org/9117009

BUG=None
TEST=None

Review URL: http://codereview.chromium.org/9465002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@123476 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 27 insertions, 5 deletions

diff --git a/ui/gfx/font.cc b/ui/gfx/font.cc
index fffaaf6..424d585 100644
--- a/ui/gfx/font.cc
+++ b/ui/gfx/font.cc
@@ -5,7 +5,6 @@
 #include "ui/gfx/font.h"
 
 #include "base/utf_string_conversions.h"
-#include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/platform_font.h"
 
 namespace gfx {
@@ -60,7 +59,7 @@ int Font::GetAverageCharacterWidth() const {
 }
 
 int Font::GetStringWidth(const string16& text) const {
-  return CanvasSkia::GetStringWidth(text, *this);
+  return platform_font_->GetStringWidth(text);
 }
 
 int Font::GetExpectedTextWidth(int length) const {
diff --git a/ui/gfx/platform_font.h b/ui/gfx/platform_font.h
index 190b421..b90d05b 100644
--- a/ui/gfx/platform_font.h
+++ b/ui/gfx/platform_font.h
@@ -47,6 +47,10 @@ class UI_EXPORT PlatformFont : public base::RefCounted<PlatformFont> {
   // Returns the average character width for the font.
   virtual int GetAverageCharacterWidth() const = 0;
 
+  // Returns the number of horizontal pixels needed to display the specified
+  // string.
+  virtual int GetStringWidth(const string16& text) const = 0;
+
   // Returns the expected number of horizontal pixels needed to display the
   // specified length of characters. Call GetStringWidth() to retrieve the
   // actual number.
diff --git a/ui/gfx/platform_font_mac.h b/ui/gfx/platform_font_mac.h
index c29b4c7..6e89cb3 100644
--- a/ui/gfx/platform_font_mac.h
+++ b/ui/gfx/platform_font_mac.h
@@ -24,6 +24,7 @@ class PlatformFontMac : public PlatformFont {
   virtual int GetHeight() const OVERRIDE;
   virtual int GetBaseline() const OVERRIDE;
   virtual int GetAverageCharacterWidth() const OVERRIDE;
+  virtual int GetStringWidth(const string16& text) const OVERRIDE;
   virtual int GetExpectedTextWidth(int length) const OVERRIDE;
   virtual int GetStyle() const OVERRIDE;
   virtual std::string GetFontName() const OVERRIDE;
diff --git a/ui/gfx/platform_font_mac.mm b/ui/gfx/platform_font_mac.mm
index 898ab57..d433f7b 100644
--- a/ui/gfx/platform_font_mac.mm
+++ b/ui/gfx/platform_font_mac.mm
@@ -10,6 +10,7 @@
 #include "base/memory/scoped_nsobject.h"
 #include "base/sys_string_conversions.h"
 #include "base/utf_string_conversions.h"
+#include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/font.h"
 
 namespace gfx {
@@ -55,6 +56,11 @@ int PlatformFontMac::GetAverageCharacterWidth() const {
   return average_width_;
 }
 
+int PlatformFontMac::GetStringWidth(const string16& text) const {
+  return CanvasSkia::GetStringWidth(text,
+                                    Font(const_cast<PlatformFontMac*>(this)));
+}
+
 int PlatformFontMac::GetExpectedTextWidth(int length) const {
   return length * average_width_;
 }
diff --git a/ui/gfx/platform_font_pango.cc b/ui/gfx/platform_font_pango.cc
index 5037829..70e7680 100644
--- a/ui/gfx/platform_font_pango.cc
+++ b/ui/gfx/platform_font_pango.cc
@@ -234,6 +234,11 @@ int PlatformFontPango::GetAverageCharacterWidth() const {
   return SkScalarRound(average_width_pixels_);
 }
 
+int PlatformFontPango::GetStringWidth(const string16& text) const {
+  return CanvasSkia::GetStringWidth(text,
+                                    Font(const_cast<PlatformFontPango*>(this)));
+}
+
 int PlatformFontPango::GetExpectedTextWidth(int length) const {
   double char_width = const_cast<PlatformFontPango*>(this)->GetAverageWidth();
   return round(static_cast<float>(length) * char_width);
@@ -393,9 +398,8 @@ void PlatformFontPango::InitPangoMetrics() {
 
     // Yes, this is how Microsoft recommends calculating the dialog unit
     // conversions.
-    const int text_width_pixels = CanvasSkia::GetStringWidth(
-        ASCIIToUTF16("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"),
-        Font(this));
+    const int text_width_pixels = GetStringWidth(
+        ASCIIToUTF16("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"));
     const double dialog_units_pixels = (text_width_pixels / 26 + 1) / 2;
     average_width_pixels_ = std::min(pango_width_pixels, dialog_units_pixels);
     pango_font_description_free(pango_desc);
diff --git a/ui/gfx/platform_font_pango.h b/ui/gfx/platform_font_pango.h
index 3161966..7e154f5 100644
--- a/ui/gfx/platform_font_pango.h
+++ b/ui/gfx/platform_font_pango.h
@@ -44,6 +44,7 @@ class UI_EXPORT PlatformFontPango : public PlatformFont {
   virtual int GetHeight() const OVERRIDE;
   virtual int GetBaseline() const OVERRIDE;
   virtual int GetAverageCharacterWidth() const OVERRIDE;
+  virtual int GetStringWidth(const string16& text) const OVERRIDE;
   virtual int GetExpectedTextWidth(int length) const OVERRIDE;
   virtual int GetStyle() const OVERRIDE;
   virtual std::string GetFontName() const OVERRIDE;
diff --git a/ui/gfx/platform_font_win.cc b/ui/gfx/platform_font_win.cc
index 1cca192..532b7b4 100644
--- a/ui/gfx/platform_font_win.cc
+++ b/ui/gfx/platform_font_win.cc
@@ -13,6 +13,7 @@
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "base/win/win_util.h"
+#include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/font.h"
 
 namespace {
@@ -101,6 +102,11 @@ int PlatformFontWin::GetAverageCharacterWidth() const {
   return font_ref_->ave_char_width();
 }
 
+int PlatformFontWin::GetStringWidth(const string16& text) const {
+  return CanvasSkia::GetStringWidth(text,
+                                    Font(const_cast<PlatformFontWin*>(this)));
+}
+
 int PlatformFontWin::GetExpectedTextWidth(int length) const {
   return length * std::min(font_ref_->dlu_base_x(), GetAverageCharacterWidth());
 }
diff --git a/ui/gfx/platform_font_win.h b/ui/gfx/platform_font_win.h
index ce23105..0e770fb 100644
--- a/ui/gfx/platform_font_win.h
+++ b/ui/gfx/platform_font_win.h
@@ -46,6 +46,7 @@ class UI_EXPORT PlatformFontWin : public PlatformFont {
   virtual int GetHeight() const OVERRIDE;
   virtual int GetBaseline() const OVERRIDE;
   virtual int GetAverageCharacterWidth() const OVERRIDE;
+  virtual int GetStringWidth(const string16& text) const OVERRIDE;
   virtual int GetExpectedTextWidth(int length) const OVERRIDE;
   virtual int GetStyle() const OVERRIDE;
   virtual std::string GetFontName() const OVERRIDE;