On the 32-bit system, if using 4k test clip, an "out of memory" error
occurred because of the AddressSanitizer instrumentation memory overhead.
In this patch, reduced the test clip's resolution while testing on 32-bit
system and AddressSanitizer is enabled.

BUG=aomedia:475

Change-Id: I4aa21b5d78e361e2ff68071064eef71b7314c1e3