Fixes layout of composite CustomButton views
Fixes layout of composite CustomButton views

Missing call to View::Layout() implementation was causing a view to not
layout its child views.

BUG=563892
TBR=sadrul

Review URL: https://codereview.chromium.org/1491173002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#362658}

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