GitLab

WebContents::GetDelegate() can return nullptr when handling a keyboard
event.

BUG=b:64863368
TEST=While browsing a PDF with an ARC Custom Tab, press Ctrl and verify
no crash occurs

Change-Id: I113a41d23f27409d52bcfe313cb4142f7562f905
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1645816Reviewed-by: Ehsan Karamad <ekaramad@chromium.org>
Commit-Queue: Jesse Schettler <jschettler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#666333}