XMLHttpRequest: return null upon failing responseArrayBuffer allocation.
The allocation of a response ArrayBuffer may fail, a large enough
contiguous chunk of memory simply not being available from the
underlying allocator. The spec [1] now admits allocation failure as a
possibility, allowing the return of a null buffer if so.
Update our implementation accordingly, returning null rather than
failing hard with an OOM.
1 - https://xhr.spec.whatwg.org/#arraybuffer-response
R=haraken,yhirano
BUG=673211
Review-Url: https://codereview.chromium.org/2730943002
Cr-Commit-Position: refs/heads/master@{#455398}
7 files changed
