Suppress an uninitialized access in gdk_pixbuf.

Started here:
http://build.chromium.org/p/chromium.memory.fyi/builders/Linux%20Tests%20%28valgrind%29%282%29/builds/32487

Nothing related in the blamelist, but given that we already have many similar
suppressions, adding one more seems fine.

BUG=176889
TBR=thestig@chromium.org

Review URL: https://codereview.chromium.org/80823002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236497 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236497
Revert 236464 "Update serial API."

Since XP bots started failing mysteriously, not being able even execute
browser_tests.

> Update serial API.
> 
> Original review: https://codereview.chromium.org/27246008/
> 
> Modified to prevent invalid API calls on Windows XP and avoid ~150kB size increase on Mac by removing IOKit dependency.
> 
> R=miket@chromium.org, rpaquay@chromium.org
> BUG=155861,148741,140125,169555,171948,281908
> 
> Review URL: https://codereview.chromium.org/79203003

TBR=rockot@chromium.org

Review URL: https://codereview.chromium.org/80833002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236498 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236498