Reland: Bailing out if pc factory fails to get created.
Reland: Bailing out if pc factory fails to get created.

This was reverted, but it turned out GOMA was down.

This prevents us from continuing if we fail initialization.
The failure will happen closer to its source, rather than
when we try to create the first peer connection.

BUG=None
R=glaznev@webrtc.org

Committed: https://crrev.com/6eb75d9e67f02c256436eb96f3c77026486561a1
Cr-Commit-Position: refs/heads/master@{#9948}

Review URL: https://codereview.webrtc.org/1339923004 .

Cr-Original-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#9974}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: fdd1b9a58e4ffbd1442f7d5b1a0bc9c602a8ed5f

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