Remove unsafe getFontMetrics methods

third_party/WebKit/Source/core/layout/LayoutBlockFlowLine.cpp

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc.
  *               All right reserved.
  * Copyright (C) 2010 Google Inc. 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
  * version 2 of the License, or (at your option) any later version.
@@ skipping 603 matching lines @@
   // measured width to 0 and adjust glyph bounds accordingly to cover the
   // overflow.
   if (measuredWidth < 0) {
     if (measuredWidth < glyphBounds.x()) {
       glyphBounds.expand(glyphBounds.x() - measuredWidth, 0);
       glyphBounds.setX(measuredWidth);
     }
     measuredWidth = 0;
   }
 
-  glyphOverflow.setFromBounds(glyphBounds, font.getFontMetrics().floatAscent(),
-                              font.getFontMetrics().floatDescent(),
-                              measuredWidth);
+  const SimpleFontData* fontData = font.primaryFont();
+  DCHECK(fontData);
+  glyphOverflow.setFromBounds(
+      glyphBounds, fontData ? fontData->getFontMetrics().floatAscent() : 0,
+      fontData ? fontData->getFontMetrics().floatDescent() : 0, measuredWidth);
 
   run->m_box->setLogicalWidth(LayoutUnit(measuredWidth) + hyphenWidth);
   if (!fallbackFonts.isEmpty()) {
     ASSERT(run->m_box->isText());
     GlyphOverflowAndFallbackFontsMap::ValueType* it =
         textBoxDataMap
             .add(toInlineTextBox(run->m_box),
                  std::make_pair(Vector<const SimpleFontData*>(),
                                 GlyphOverflow()))
             .storedValue;
@@ skipping 1874 matching lines @@
 
 bool LayoutBlockFlow::paintedOutputOfObjectHasNoEffectRegardlessOfSize() const {
   // LayoutBlockFlow is in charge of paint invalidation of the first line.
   if (firstLineBox())
     return false;
 
   return LayoutBlock::paintedOutputOfObjectHasNoEffectRegardlessOfSize();
 }
 
 }  // namespace blink