Move a few functions commonly called with char* to StringPiece.

base/string_util.h

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // This file defines utility functions for working with strings.
 
 #ifndef BASE_STRING_UTIL_H_
 #define BASE_STRING_UTIL_H_
 
 #include <stdarg.h>   // va_list
@@ skipping 156 matching lines @@
 // Returns |text, with the following three transformations:
 // (1) Leading and trailing whitespace is trimmed.
 // (2) If |trim_sequences_with_line_breaks| is true, any other whitespace
 //     sequences containing a CR or LF are trimmed.
 // (3) All other whitespace sequences are converted to single spaces.
 std::wstring CollapseWhitespace(const std::wstring& text,
                                 bool trim_sequences_with_line_breaks);
 
 // These convert between ASCII (7-bit) and Wide/UTF16 strings.
 std::string WideToASCII(const std::wstring& wide);
-std::wstring ASCIIToWide(const std::string& ascii);
+std::wstring ASCIIToWide(const StringPiece& ascii);
 std::string UTF16ToASCII(const string16& utf16);
-string16 ASCIIToUTF16(const std::string& ascii);
+string16 ASCIIToUTF16(const StringPiece& ascii);
 
 // These convert between UTF-8, -16, and -32 strings. They are potentially slow,
 // so avoid unnecessary conversions. The low-level versions return a boolean
 // indicating whether the conversion was 100% valid. In this case, it will still
 // do the best it can and put the result in the output buffer. The versions that
 // return strings ignore this error and just return the best conversion
 // possible.
 bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output);
 std::string WideToUTF8(const std::wstring& wide);
 bool UTF8ToWide(const char* src, size_t src_len, std::wstring* output);
@@ skipping 55 matching lines @@
 bool WideToLatin1(const std::wstring& wide, std::string* latin1);
 
 // Returns true if the specified string matches the criteria. How can a wide
 // string be 8-bit or UTF8? It contains only characters that are < 256 (in the
 // first case) or characters that use only 8-bits and whose 8-bit
 // representation looks like a UTF-8 string (the second case).
 bool IsString8Bit(const std::wstring& str);
 bool IsStringUTF8(const std::string& str);
 bool IsStringWideUTF8(const std::wstring& str);
 bool IsStringASCII(const std::wstring& str);
-bool IsStringASCII(const std::string& str);
+bool IsStringASCII(const StringPiece& str);
 bool IsStringASCII(const string16& str);
 
 // ASCII-specific tolower.  The standard library's tolower is locale sensitive,
 // so we don't want to use it here.
 template <class Char> inline Char ToLowerASCII(Char c) {
   return (c >= 'A' && c <= 'Z') ? (c + ('a' - 'A')) : c;
 }
 
 // Converts the elements of the given string.  This version uses a pointer to
 // clearly differentiate it from the non-pointer variant.
@@ skipping 352 matching lines @@
 #elif defined(WCHAR_T_IS_UTF32)
   typedef uint32 Unsigned;
 #endif
 };
 template<>
 struct ToUnsigned<short> {
   typedef unsigned short Unsigned;
 };
 
 #endif  // BASE_STRING_UTIL_H_