Relanding this with font test fixes for gdi.

ui/gfx/platform_font_win.cc

Index: ui/gfx/platform_font_win.cc
diff --git a/ui/gfx/platform_font_win.cc b/ui/gfx/platform_font_win.cc
index 5e9d2537e5a188d88bf8b1bd186c36b50376a954..0db05c4864372ed4fff84f9a05881a72ec120227 100644
--- a/ui/gfx/platform_font_win.cc
+++ b/ui/gfx/platform_font_win.cc
@@ -211,14 +211,22 @@ PlatformFontWin::PlatformFontWin(const std::string& font_name,
 
 Font PlatformFontWin::DeriveFontWithHeight(int height, int style) {
   DCHECK_GE(height, 0);
-  if (GetHeight() == height && GetStyle() == style)
-    return Font(this);
+
+  // Create a font with a height near that of the target height.
+  LOGFONT font_info;
+  GetObject(GetNativeFont(), sizeof(LOGFONT), &font_info);
+  font_info.lfHeight = height;
+  SetLogFontStyle(style, &font_info);
+
+  HFONT hfont = CreateFontIndirect(&font_info);
+  Font font(new PlatformFontWin(CreateHFontRef(hfont)));
+
+  const int min_font_size = GetMinimumFontSize();
 
   // CreateFontIndirect() doesn't return the largest size for the given height
   // when decreasing the height. Iterate to find it.
-  if (GetHeight() > height) {
-    const int min_font_size = GetMinimumFontSize();
-    Font font = DeriveFont(-1, style);
+  if (font.GetHeight() > height) {

[msw, 2015/01/13 21:59:57]

This check could potentially return a font smaller than the min size. If
|height|=10, |min_font_size|==10, |font.GetHeight()|==11,
|font.GetFontSize()|==9, this if statement would pass; then the first Derive
statement could make: |font.GetHeight()|==10, |font.GetFontSize()|==8, which
would skip the while loop and return the |font| at size 8, smaller than the min
size of 10. Let's rewrite this loop to handle that case and match the structure
of the new loop below. Does this look right?

while ((font.GetHeight() > height) &&
       (font.GetFontSize() >= min_font_size)) {
  Font derived_font = font.Derive(-1, style);
  if ((derived_font.GetFontSize() < min_font_size) ||
      (derived_font.GetFontSize() == font.GetFontSize()))
    break;
  DCHECK_LT(derived_font.GetFontSize(), font.GetFontSize());
  font = derived_font;
}

[ananta, 2015/01/13 22:21:46]

Yes. I put this block inside an if (font.GetHeight() > height).

+    font = font.Derive(-1, style);
     int font_height = font.GetHeight();
     int font_size = font.GetFontSize();
     while (font_height > height && font_size != min_font_size) {
@@ -231,13 +239,16 @@ Font PlatformFontWin::DeriveFontWithHeight(int height, int style) {
     return font;
   }
 
-  LOGFONT font_info;
-  GetObject(GetNativeFont(), sizeof(LOGFONT), &font_info);
-  font_info.lfHeight = height;
-  SetLogFontStyle(style, &font_info);
-
-  HFONT hfont = CreateFontIndirect(&font_info);
-  return DeriveWithCorrectedSize(hfont);
+  // Respect the minimum font size constraint.

[msw, 2015/01/13 21:59:57]

nit: move this comment just above the |min_font_size| decl.

[ananta, 2015/01/13 22:21:46]

Done.

+  while ((font.GetHeight() <= height) ||
+         (font.GetFontSize() < min_font_size)) {
+    Font derived_font = font.Derive(1, style);
+    if (derived_font.GetHeight() > height && !min_font_size)

[msw, 2015/01/13 21:59:57]

I think this should be:
  if ((derived_font.GetHeight() > height) &&
      (font.GetFontSize() >= min_font_size))
Otherwise, given |height|==10, |min_font_size|==5, |font.GetHeight()|=10,
|font.GetFontSize()|=7, |derived_font.GetHeight()|==11, this check as-is would
fail and we'd wind up returning the |derived_font| with a height larger than
requested, even though the |font| already passes the minimum size requirement.

[ananta, 2015/01/13 22:21:46]

Done.

[ananta, 2015/01/13 22:21:46]

Done.

+      break;
+    DCHECK_GT(derived_font.GetFontSize(), font.GetFontSize());
+    font = derived_font;
+  }
+  return font;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -423,37 +434,6 @@ PlatformFontWin::HFontRef* PlatformFontWin::CreateHFontRefFromGDI(
                       ave_char_width, style);
 }
 
-Font PlatformFontWin::DeriveWithCorrectedSize(HFONT base_font) {
-  base::win::ScopedGetDC screen_dc(NULL);
-  gfx::ScopedSetMapMode mode(screen_dc, MM_TEXT);
-
-  base::win::ScopedGDIObject<HFONT> best_font(base_font);
-  TEXTMETRIC best_font_metrics;
-  GetTextMetricsForFont(screen_dc, best_font, &best_font_metrics);
-
-  LOGFONT font_info;
-  GetObject(base_font, sizeof(LOGFONT), &font_info);
-
-  // Set |lfHeight| to negative value to indicate it's the size, not the height.
-  font_info.lfHeight =
-      -(best_font_metrics.tmHeight - best_font_metrics.tmInternalLeading);
-
-  do {
-    // Increment font size. Prefer font with greater size if its height isn't
-    // greater than height of base font.
-    font_info.lfHeight = AdjustFontSize(font_info.lfHeight, 1);
-    base::win::ScopedGDIObject<HFONT> font(CreateFontIndirect(&font_info));
-    TEXTMETRIC font_metrics;
-    GetTextMetricsForFont(screen_dc, font, &font_metrics);
-    if (font_metrics.tmHeight > best_font_metrics.tmHeight)
-      break;
-    best_font.Set(font.release());
-    best_font_metrics = font_metrics;
-  } while (true);
-
-  return Font(new PlatformFontWin(CreateHFontRef(best_font.release())));
-}
-
 // static
 PlatformFontWin::HFontRef* PlatformFontWin::CreateHFontRefFromSkia(
     HFONT gdi_font,
@@ -518,8 +498,7 @@ PlatformFontWin::HFontRef* PlatformFontWin::CreateHFontRefFromSkia(
   // The calculations below are similar to those in the CreateHFontRef
   // function. The height, baseline and cap height are rounded up to ensure
   // that they match up closely with GDI.
-  const int height = std::ceil(
-      skia_metrics.fDescent - skia_metrics.fAscent + skia_metrics.fLeading);
+  const int height = std::ceil(skia_metrics.fDescent - skia_metrics.fAscent);
   const int baseline = std::max<int>(1, std::ceil(-skia_metrics.fAscent));
   const int cap_height = std::ceil(paint.getTextSize() *
       static_cast<double>(dwrite_font_metrics.capHeight) /