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-- The DeleteAllPages method is only used by the offline internals page.
-- The Javascript can send all the request ids for DeleteAllRequests to eliminate additional async callback complexity.
-- Update IDs to be less confusing.

BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2342603004
Cr-Commit-Position: refs/heads/master@{#418968}