Fixing isWhitespace & isSpace for Client ICU

(Flutter bug https://b.corp.google.com/issues/275577777)
Apparently, Flutter uses some big values in Unicode codepoints
to code some icons into fonts.
If we search for values in string something like 0xf2008
will be found as a concatenation of two values, even when there
is no real value - which is an error.

Change-Id: Ie794d76acd27946583ef384b8f6d82ca0cec3ff0
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/666417
Commit-Queue: Julia Lavrova <jlavrova@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
2 files changed