LeakSanitizer: re-suppress some Blink leaks.

Recent suppression pruning went a little bit overboard.

BUG=328552
TBR=glider@chromium.org

Review URL: https://codereview.chromium.org/178543003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254385 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254385