Use StringView for String::find.

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2009 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 348 matching lines @@
 
     PassRefPtr<StringImpl> stripWhiteSpace();
     PassRefPtr<StringImpl> stripWhiteSpace(IsWhiteSpaceFunctionPtr);
     PassRefPtr<StringImpl> simplifyWhiteSpace(StripBehavior = StripExtraWhiteSpace);
     PassRefPtr<StringImpl> simplifyWhiteSpace(IsWhiteSpaceFunctionPtr, StripBehavior = StripExtraWhiteSpace);
 
     PassRefPtr<StringImpl> removeCharacters(CharacterMatchFunctionPtr);
     template <typename CharType>
     ALWAYS_INLINE PassRefPtr<StringImpl> removeCharacters(const CharType* characters, CharacterMatchFunctionPtr);
 
+    // Find characters.
     size_t find(LChar character, unsigned start = 0);
     size_t find(char character, unsigned start = 0);
     size_t find(UChar character, unsigned start = 0);
     size_t find(CharacterMatchFunctionPtr, unsigned index = 0);
-    size_t find(const LChar*, unsigned index = 0);
-    ALWAYS_INLINE size_t find(const char* s, unsigned index = 0) { return find(reinterpret_cast<const LChar*>(s), index); }
-    size_t find(StringImpl*);
-    size_t find(StringImpl*, unsigned index);
-    size_t findIgnoringCase(const LChar*, unsigned index = 0);
-    ALWAYS_INLINE size_t findIgnoringCase(const char* s, unsigned index = 0) { return findIgnoringCase(reinterpret_cast<const LChar*>(s), index); }
-    size_t findIgnoringCase(StringImpl*, unsigned index = 0);
-    size_t findIgnoringASCIICase(StringImpl*, unsigned index = 0);
+
+    // Find substrings.
+    size_t find(const StringView&, unsigned index = 0);
+    size_t findIgnoringCase(const StringView&, unsigned index = 0);
+    size_t findIgnoringASCIICase(const StringView&, unsigned index = 0);
 
     size_t reverseFind(UChar, unsigned index = UINT_MAX);
     size_t reverseFind(StringImpl*, unsigned index = UINT_MAX);
 
     bool startsWith(UChar) const;
     bool startsWith(const StringView&) const;
     bool startsWithIgnoringCase(const StringView&) const;
     bool startsWithIgnoringASCIICase(const StringView&) const;
 
     bool endsWith(UChar) const;
@@ skipping 322 matching lines @@
 using WTF::StringImpl;
 using WTF::TextCaseASCIIInsensitive;
 using WTF::TextCaseInsensitive;
 using WTF::TextCaseSensitive;
 using WTF::TextCaseSensitivity;
 using WTF::equal;
 using WTF::equalNonNull;
 using WTF::lengthOfNullTerminatedString;
 
 #endif