Remove wtf::String::characterAt.

third_party/WebKit/Source/wtf/text/WTFString.h

Index: third_party/WebKit/Source/wtf/text/WTFString.h
diff --git a/third_party/WebKit/Source/wtf/text/WTFString.h b/third_party/WebKit/Source/wtf/text/WTFString.h
index 90636b5dee4d9eb1fe2019b4949f74e7112082e8..27462b0bae4a295154ff9c1d26b3890647125679 100644
--- a/third_party/WebKit/Source/wtf/text/WTFString.h
+++ b/third_party/WebKit/Source/wtf/text/WTFString.h
@@ -448,14 +448,6 @@ public:
     void show() const;
 #endif
 
-    // Workaround for a compiler bug. Use operator[] instead.
-    UChar characterAt(unsigned index) const
-    {
-        if (!m_impl || index >= m_impl->length())
-            return 0;
-        return (*m_impl)[index];
-    }
-
 private:
     typedef struct ImplicitConversionFromWTFStringToBoolDisallowed* (String::*UnspecifiedBoolType);
     operator UnspecifiedBoolType() const;