Worker: Rename WorkerScriptLoader to WorkerClassicScriptLoader

This CL renames WorkerScriptLoader to WorkerClassicScriptLoader for clarifying
the loader is used for classic scripts, not for module scripts.

Bug: 680046
Change-Id: I037de4772e8323e4176989427fa6c2529c7fdab0
Reviewed-on: https://chromium-review.googlesource.com/965662
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Commit-Queue: Hiroki Nakagawa <nhiroki@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543651}
13 files changed