Connect the LocalDB to TabManager.

Bug: 773382
Change-Id: Iec8fe5226ee175105d51f300f30b4865478ac099
Reviewed-on: https://chromium-review.googlesource.com/1118611
Commit-Queue: Sébastien Marchand <sebmarchand@chromium.org>
Reviewed-by: François Doray <fdoray@chromium.org>
Cr-Commit-Position: refs/heads/master@{#572871}
void TabLifecycleUnitSource::TabLifecycleUnit::SetWebContents(
    content::WebContents* web_contents) {
  DCHECK(web_contents);
  Observe(web_contents);
}

void TabLifecycleUnitSource::TabLifecycleUnit::SetWebContents(
    content::WebContents* web_contents) {
  DCHECK(web_contents);
  Observe(web_contents);
}
