Fork: Limit async upload memory to 6MB

This is the same change for webview as upstream chromium
crrev.com/r290764. However the upstream change is large and has
conflicts, so this is a smaller change. This should not be submitted to
upstream chromium.

BUG: 16550863
Change-Id: I84dfeea7c3bbe7827b0741e62e9cbb59ef39d7b2
1 file changed