Hide app list view on ARC app launch from app-launcher view.
Hide app list view on ARC app launch from app-launcher view.

BUG=567520
TEST=unit_tests passed
TEST=Start Chrome, manually click on ready ARC app item in
     app-launcher. ARC app is started and app list view is
     automatically closed.

Review URL: https://codereview.chromium.org/1562863002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#367990}

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