base: get rid of deprecated TrimWhitespace() function

base/strings/string_util.h

Index: base/strings/string_util.h
diff --git a/base/strings/string_util.h b/base/strings/string_util.h
index 3976111b74560fa64dec235f5b2b5a4afe4c56d3..af7b6e6ae9fd374766d43af828491c449265c4cd 100644
--- a/base/strings/string_util.h
+++ b/base/strings/string_util.h
@@ -243,12 +243,6 @@ BASE_EXPORT TrimPositions TrimWhitespaceASCII(const std::string& input,
 BASE_EXPORT StringPiece TrimWhitespaceASCII(StringPiece input,
                                             TrimPositions positions);
 
-// Deprecated. This function is only for backward compatibility and calls
-// TrimWhitespaceASCII().
-BASE_EXPORT TrimPositions TrimWhitespace(const std::string& input,
-                                         TrimPositions positions,
-                                         std::string* output);
-
 // Searches  for CR or LF characters.  Removes all contiguous whitespace
 // strings that contain them.  This is useful when trying to deal with text
 // copied from terminals.