Move RemoveChars, ReplaceChars, TrimString, and TruncateUTF8ToByteSize to base namespace.

net/base/mime_util.cc

Index: net/base/mime_util.cc
diff --git a/net/base/mime_util.cc b/net/base/mime_util.cc
index 8eba45ac101ff71cf6d273ab2de00d1e386498a6..b1ebfecf63b879021c04199c5f426c1acab0bbc8 100644
--- a/net/base/mime_util.cc
+++ b/net/base/mime_util.cc
@@ -668,7 +668,7 @@ void MimeUtil::ParseCodecString(const std::string& codecs,
                                 std::vector<std::string>* codecs_out,
                                 bool strip) {
   std::string no_quote_codecs;
-  TrimString(codecs, "\"", &no_quote_codecs);
+  base::TrimString(codecs, "\"", &no_quote_codecs);
   base::SplitString(no_quote_codecs, ',', codecs_out);
 
   if (!strip)