Remove unsafe getFontMetrics methods

third_party/WebKit/Source/core/css/resolver/FontBuilder.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc.
  * All rights reserved.
  * Copyright (C) 2013 Google Inc. All rights reserved.
  * Copyright (C) 2015 Collabora Ltd. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 301 matching lines @@
     return;
 
   // We need to create a temporal Font to get xHeight of a primary font.
   // The aspect value is based on the xHeight of the font for the computed font
   // size, so we need to reset the adjustedSize to computedSize. See
   // FontDescription::effectiveFontSize.
   fontDescription.setAdjustedSize(fontDescription.computedSize());
 
   Font font(fontDescription);
   font.update(fontSelector);
-  if (!font.getFontMetrics().hasXHeight())
+
+  const SimpleFontData* fontData = font.primaryFont();
+
+  if (!fontData || !fontData->getFontMetrics().hasXHeight())
     return;
 
   const float sizeAdjust = fontDescription.sizeAdjust();
-  float aspectValue = font.getFontMetrics().xHeight() / specifiedSize;
+  float aspectValue = fontData->getFontMetrics().xHeight() / specifiedSize;
   float adjustedSize = (sizeAdjust / aspectValue) * specifiedSize;
   adjustedSize = getComputedSizeFromSpecifiedSize(
       fontDescription, style.effectiveZoom(), adjustedSize);
 
   float multiplier = style.textAutosizingMultiplier();
   adjustedSize =
       TextAutosizer::computeAutosizedFontSize(adjustedSize, multiplier);
   fontDescription.setAdjustedSize(adjustedSize);
 }
 
@@ skipping 70 matching lines @@
           FontDescription::Size(FontSize::initialKeywordSize(), 0.0f, false));
   updateSpecifiedSize(fontDescription, documentStyle);
   updateComputedSize(fontDescription, documentStyle);
 
   updateOrientation(fontDescription, documentStyle);
   documentStyle.setFontDescription(fontDescription);
   documentStyle.font().update(fontSelector);
 }
 
 }  // namespace blink