Remove unsafe getFontMetrics methods

third_party/WebKit/Source/core/svg/SVGLengthContext.cpp

Index: third_party/WebKit/Source/core/svg/SVGLengthContext.cpp
diff --git a/third_party/WebKit/Source/core/svg/SVGLengthContext.cpp b/third_party/WebKit/Source/core/svg/SVGLengthContext.cpp
index 2670221a4c2a590ac206e0a08d65c43cd50bd97d..bd4cf089796b580dc03810a7fd2d4dcd88b938b4 100644
--- a/third_party/WebKit/Source/core/svg/SVGLengthContext.cpp
+++ b/third_party/WebKit/Source/core/svg/SVGLengthContext.cpp
@@ -373,11 +373,12 @@ float SVGLengthContext::convertValueFromUserUnits(
 
 float SVGLengthContext::convertValueFromUserUnitsToCHS(float value) const {
   const ComputedStyle* style = computedStyleForLengthResolving(m_context);
-  if (!style)
+  const SimpleFontData* fontData = style->font().primaryFont();
+  if (!style || !fontData)
     return 0;
 
   float zeroWidth =
-      style->getFontMetrics().zeroWidth() / style->effectiveZoom();
+      fontData->getFontMetrics().zeroWidth() / style->effectiveZoom();
   if (!zeroWidth)
     return 0;
 
@@ -386,22 +387,25 @@ float SVGLengthContext::convertValueFromUserUnitsToCHS(float value) const {
 
 float SVGLengthContext::convertValueFromCHSToUserUnits(float value) const {
   const ComputedStyle* style = computedStyleForLengthResolving(m_context);
-  if (!style)
+  const SimpleFontData* fontData = style->font().primaryFont();
+  if (!style || !fontData)
     return 0;
 
-  return value * style->getFontMetrics().zeroWidth() / style->effectiveZoom();
+  return value * fontData->getFontMetrics().zeroWidth() /
+         style->effectiveZoom();
 }
 
 float SVGLengthContext::convertValueFromUserUnitsToEXS(float value) const {
   const ComputedStyle* style = computedStyleForLengthResolving(m_context);
-  if (!style)
+  const SimpleFontData* fontData = style->font().primaryFont();
+  if (!style || !fontData)
     return 0;
 
   // Use of ceil allows a pixel match to the W3Cs expected output of
   // coords-units-03-b.svg, if this causes problems in real world cases maybe it
   // would be best to remove this.
   float xHeight =
-      ceilf(style->getFontMetrics().xHeight() / style->effectiveZoom());
+      ceilf(fontData->getFontMetrics().xHeight() / style->effectiveZoom());
   if (!xHeight)
     return 0;
 
@@ -410,14 +414,15 @@ float SVGLengthContext::convertValueFromUserUnitsToEXS(float value) const {
 
 float SVGLengthContext::convertValueFromEXSToUserUnits(float value) const {
   const ComputedStyle* style = computedStyleForLengthResolving(m_context);
-  if (!style)
+  const SimpleFontData* fontData = style->font().primaryFont();
+  if (!style || !fontData)
     return 0;
 
   // Use of ceil allows a pixel match to the W3Cs expected output of
   // coords-units-03-b.svg, if this causes problems in real world cases maybe it
   // would be best to remove this.
   return value *
-         ceilf(style->getFontMetrics().xHeight() / style->effectiveZoom());
+         ceilf(fontData->getFontMetrics().xHeight() / style->effectiveZoom());
 }
 
 bool SVGLengthContext::determineViewport(FloatSize& viewportSize) const {