Introduce String::fromUTF8Lenient() and use it for cache_name in CacheStorage API.

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

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple 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.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 410 matching lines @@
 
     static String make8BitFrom16BitSource(const UChar*, size_t);
     template<size_t inlineCapacity>
     static String make8BitFrom16BitSource(const Vector<UChar, inlineCapacity>& buffer)
     {
         return make8BitFrom16BitSource(buffer.data(), buffer.size());
     }
 
     static String make16BitFrom8BitSource(const LChar*, size_t);
 
-    // String::fromUTF8 will return a null string if
-    // the input data contains invalid UTF-8 sequences.
-    static String fromUTF8(const LChar*, size_t);
+    // String::fromUTF8 will return a null string if the input data contains
+    // invalid UTF-8 sequences. When |strict| is false, isolated surrogates are
+    // converted.
+    static String fromUTF8(const LChar*, size_t, bool strict = true);
     static String fromUTF8(const LChar*);
     static String fromUTF8(const char* s, size_t length) { return fromUTF8(reinterpret_cast<const LChar*>(s), length); }
     static String fromUTF8(const char* s) { return fromUTF8(reinterpret_cast<const LChar*>(s)); }
     static String fromUTF8(const CString&);
 
     // Tries to convert the passed in string to UTF-8, but will fall back to
     // Latin-1 if the string is not valid UTF-8.
     static String fromUTF8WithLatin1Fallback(const LChar*, size_t);
     static String fromUTF8WithLatin1Fallback(const char* s, size_t length) { return fromUTF8WithLatin1Fallback(reinterpret_cast<const LChar*>(s), length); }
 
+    // Helper methods to call fromUTF8() with |strict| = false.
+    static String fromUTF8Lenient(const LChar* s, size_t length) { return fromUTF8(s, length, false); }
+    static String fromUTF8Lenient(const char* s, size_t length) { return fromUTF8Lenient(reinterpret_cast<const LChar*>(s), length); }
+
     bool containsOnlyASCII() const;
     bool containsOnlyLatin1() const;
     bool containsOnlyWhitespace() const { return !m_impl || m_impl->containsOnlyWhitespace(); }
 
     // Hash table deleted values, which are only constructed and never copied or
     // destroyed.
     String(WTF::HashTableDeletedValueType) : m_impl(WTF::HashTableDeletedValue) { }
     bool isHashTableDeletedValue() const { return m_impl.isHashTableDeletedValue(); }
 
 #ifndef NDEBUG
@@ skipping 252 matching lines @@
 using WTF::charactersToFloat;
 using WTF::equal;
 using WTF::equalIgnoringCase;
 using WTF::find;
 using WTF::isAllSpecialCharacters;
 using WTF::isSpaceOrNewline;
 using WTF::reverseFind;
 
 #include "wtf/text/AtomicString.h"
 #endif // WTFString_h