Revert of Do not activate TrayBubbleView by default (patchset #15 id:270001 of https://codereview.chromium.org/2897553002/ )

Reason for revert:
Speculative revert. I suspect this broke the interactive_ui_tests on Linux ChromiumOS MSan Tests (https://build.chromium.org/p/chromium.memory/builders/Linux%20ChromiumOS%20MSan%20Tests/builds/1276). The tests now time out, and the log contains lines with:

Still waiting for the following processes to finish:
	./interactive_ui_tests --brave-new-test-launcher --cfi-diag=0 --gtest_also_run_disabled_tests --gtest_filter=TestAsNormalAndGuestUser/SpokenFeedbackTest.NavigateSystemTray/0 --single_process --test-launcher-bot-mode --test-launcher-print-test-stdio=always --test-launcher-summary-output=/b/s/w/ioS9oZeu/output.json --user-data-dir=/b/s/w/it1bN0Em/.org.chromium.Chromium.iOqw8e/dOj481Q

Original issue's description:
> Do not activate TrayBubbleView by default
>
> - Activating a TrayBubbleView brings an Android window to onPause state.
> - This CL sets can_set_activate to false and makes TrayBubbleView not
>   activated by default.
> - If the TrayBubbleView is not activated, it cannot capture key events
>   for moving focus or closing the view by keyboard. TrayBubbleView tries
>   to register accelerators at the global level to capture those key
>   events.
> - Activates the TrayBubbleView by default if keyboard navigation
>   accessibility feature (e.g. spoken feedback) is enabled.
>
> BUG=726588,731748
> TEST=Follow steps described in the issue
>
> Review-Url: https://codereview.chromium.org/2897553002
> Cr-Commit-Position: refs/heads/master@{#481421}
> Committed: https://chromium.googlesource.com/chromium/src/+/c97f341f1a2f6f359ba1a7c8687aa58af6f7033c

TBR=stevenjb@chromium.org,dmazzoni@chromium.org,msw@chromium.org,jamescook@chromium.org,yawano@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=726588,731748

Review-Url: https://codereview.chromium.org/2948223002
Cr-Commit-Position: refs/heads/master@{#481485}