libwep: cherry-pick fix for compilation to arm64

c1cb193 disable NEON for arm64 platform

BUG=314720, 342387
R=urvang@google.com
TBR=cpu@chromium.org

Review URL: https://codereview.chromium.org/153273005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251047 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251047
Change streamsPrivate to use an IDL definition file.

BUG=343006

Review URL: https://codereview.chromium.org/132793014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251048 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251048