Store and retrieve features from shared memory
If using shared memory, stores base::Features in the field trial
allocator (under a different type defined in FeatureList) when
spawning the first new process. When a child process is created,
it will first try to get initialized from shared memory. If that
doesn't work, it'll fallback to the command line.
BUG=661224
Review-Url: https://codereview.chromium.org/2546653002
Cr-Commit-Position: refs/heads/master@{#436311}
8 files changed
