DevTools: Remove unused CodeMirrorCSSLoadView
DevTools: Remove unused CodeMirrorCSSLoadView

This code was not used

Change-Id: I57c742e34811807e091d8a833fa89ac0487e64bf
Reviewed-on: https://chromium-review.googlesource.com/c/1356128
Reviewed-by: Dmitry Gozman <0ca14b32cbb359a30ac562af27dd84cc2813eacb@chromium.org>
Commit-Queue: Joel Einbinder <bab755abe9fee48fe544272e55f73517d4e4a725@chromium.org>
Cr-Original-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#612771}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: e07270b2456fa982686c3bb9d77f244c7628d62f
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