This commit has no behavior changes.
In particular, this does not fix any of the wrong uses of the previous
default parameter (which used to be 'false', meaning "only replace the
first occurence in the string"). It simply replaces the default uses by
String::replace(..., ReplaceMode::FirstOnly), leaving them incorrect.
The main thing that is missing is validating certain pieces of data
against XML productions in well-formed mode, but nothing uses
well-formed mode right now.
Required by Closure Library for sanitising HTML.
e687b3d8ab/closure/goog/html/sanitizer/safedomtreeprocessor.js (L117)