GitLab

Move the available memory calculation from kernel to chrome.  Use
polling to check low memory condition instead of waiting for kernel low
memory notification.

BUG=b:149833548
TEST=run chromeos tast platform.MemoryStressBasic

Change-Id: I2c21bddfc261727265c65420d143ad428501ca93
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2058945
Commit-Queue: Kuo-Hsin Yang <vovoy@chromium.org>
Reviewed-by: Yusuke Sato <yusukes@chromium.org>
Reviewed-by: François Doray <fdoray@chromium.org>
Reviewed-by: Brian Geffon <bgeffon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#745718}