Move //components/omnibox into //components/omnibox/browser
//chrome/common/omnibox_focus_state.h needs to be componentized, as it is used
by //chrome/browser/ui/omnibox code. As it's also used by //chrome/renderer, it
needs to be componentized into //components/omnibox/common so that DEPS
allowances/build dependencies have the expected structure (i.e., don't allow
for bleed between renderer and browser code).
BUG=371536
TBR=sky
Review URL: https://codereview.chromium.org/
1229613004
Cr-Commit-Position: refs/heads/master@{#338007}