Revert "Revert "ASCII <-> UTF16 conversion functions. These are just copies of WideToASCII and""

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 <string>
@@ skipping 138 matching lines @@
 // strings that contain them.  This is useful when trying to deal with text
 // copied from terminals.
 // 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 UTF16 strings.
+// 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::string UTF16ToASCII(const string16& utf16);
+string16 ASCIIToUTF16(const std::string& 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 56 matching lines @@
 
 // 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 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.
 template <class str> inline void StringToLowerASCII(str* s) {
@@ skipping 318 matching lines @@
 // Returns a hex string representation of a binary buffer.
 // The returned hex string will be in upper case.
 // This function does not check if |size| is within reasonable limits since
 // it's written with trusted data in mind.
 // If you suspect that the data you want to format might be large,
 // the absolute max size for |size| should be is
 //   std::numeric_limits<size_t>::max() / 2
 std::string HexEncode(const void* bytes, size_t size);
 
 #endif  // BASE_STRING_UTIL_H_