Use MEMORY_SANITIZER_INITIAL_SIZE for sanitizer.

Out-of-bounds reads based on pointer access.
so the initial size should be 1 at instance time.
This patch is related with crrev.com/357603002
and the original issue was crrev.com/22548004.

Bug=None

Review URL: https://codereview.chromium.org/360693002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@280862 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed