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

BUG=
R=viettrungluu@chromium.org

Review URL: https://codereview.chromium.org/102843002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238465 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 238465