Picture in picture does not render the video controls overlay when hovering on the video

[pedrotari7]

Describe the bug
When playing video in picture-in-picture the playback works as expected, however when hovering on the window, CEF is not able to render the usual overlay containing the native controls, and instead renders the fallback red tile. This happens when running in the client sample app of CEF but not in similar versions of chrome.

To Reproduce
Steps to reproduce the behaviour:

1. Go to a webpage with a video element with a picture-in-picture toggle available example
2. Click on 'the PiP toggle'
3. Hover on the floating window
4. See error

Expected behaviour
The native video element controls should appear on hover

Screenshots
Playback:

OnHover:

Versions (please complete the following information):

• OS: MacOS 13.3.1
• CEF Version: 111.2.7+gebf5d6a+chromium-111.0.5563.148

Additional context
Does the problem reproduce with Google Chrome at the same version?
No

[magreenblatt]

This also reproduces on Windows 10 with current master (M113). Mouseover of the PiP window shows cursor changes and clicking the link works as expected, so this is likely a rendering issue. Does not reproduce when using --enable-chrome-runtime.

[magreenblatt]

Looks like this broke in M101/M102 (working in 100, partially broken in 101 (red text/button regions), fully broken in 102 (red content area))

[magreenblatt]

Looks like ColorProvider in video_overlay_window_views.cc is returning solid red (kPlaceholderColor) instead of the expected theme color kColorPipWindowControlsBackground which has an alpha component.

[magreenblatt]

Alloy needs to initialize the Chrome color mixer as shown in https://chromium.googlesource.com/chromium/src/+/e959940a7e4830a492dac6a5a6e9f143970e40f6%5E%21/#F1