Linux: Align stack access for 32-bit Clang builds.

BUG=418554
TEST=Manual, see bug.
NOTRY=true

Review URL: https://codereview.chromium.org/638833002

Cr-Commit-Position: refs/heads/master@{#298755}
(cherry picked from commit a9c2f07f60b7b2c9dba1db21717c5445c98828f0)

Review URL: https://codereview.chromium.org/644533002

Cr-Commit-Position: refs/branch-heads/2125@{#560}
Cr-Branched-From: b68026d94bda36dd106a3d91a098719f952a9477-refs/heads/master@{#290040}
1 file changed