Fix context menu and floating bar styles for dark mode

+ Set alertDialogTheme so that context menu can inherit
+ Use applyOverideConfiguration for ChromeActivity except CCT
+ Add force apply style to workaround wrong styles

Bug: 935731
Change-Id: I08959b089040bf0b294bef8de0b0018867cfee10
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1512783
Commit-Queue: Becky Zhou <huayinz@chromium.org>
Reviewed-by: Theresa <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#639741}
11 files changed