Compute min-content width when hyphenation is enabled

third_party/WebKit/Source/platform/text/Hyphenation.h

Index: third_party/WebKit/Source/platform/text/Hyphenation.h
diff --git a/third_party/WebKit/Source/platform/text/Hyphenation.h b/third_party/WebKit/Source/platform/text/Hyphenation.h
index bd86f5ae610c76c9eb71bf612134fbf6ba837d50..2a22bfde7d2a6b5bf662cd7f60759156de52ebc7 100644
--- a/third_party/WebKit/Source/platform/text/Hyphenation.h
+++ b/third_party/WebKit/Source/platform/text/Hyphenation.h
@@ -6,6 +6,7 @@
 #define Hyphenation_h
 
 #include "platform/PlatformExport.h"
+#include "platform/fonts/Font.h"
 #include "wtf/Forward.h"
 #include "wtf/HashMap.h"
 #include "wtf/RefCounted.h"
@@ -21,6 +22,11 @@ public:
     static Hyphenation* get(const AtomicString& locale);
 
     virtual size_t lastHyphenLocation(const StringView&, size_t beforeIndex) const = 0;
+    virtual Vector<size_t, 8> hyphenLocations(const StringView&) const;
+
+    static const unsigned minimumPrefixLength = 2;
+    static const unsigned minimumSuffixLength = 2;
+    static int minimumPrefixWidth(const Font&);
 
     static void setForTesting(const AtomicString& locale, PassRefPtr<Hyphenation>);
     static void clearForTesting();
@@ -32,6 +38,17 @@ private:
     static PassRefPtr<Hyphenation> platformGetHyphenation(const AtomicString& locale);
 };
 
+inline int Hyphenation::minimumPrefixWidth(const Font& font)
+{
+    // If the maximum width available for the prefix before the hyphen is small, then it is very unlikely
+    // that an hyphenation opportunity exists, so do not bother to look for it.
+    // These are heuristic numbers for performance added in http://wkb.ug/45606
+    const int minimumPrefixWidthNumerator = 5;
+    const int minimumPrefixWidthDenominator = 4;
+    return font.getFontDescription().computedPixelSize()
+        * minimumPrefixWidthNumerator / minimumPrefixWidthDenominator;
+}
+
 } // namespace blink
 
 #endif // Hyphenation_h