[Output Switcher] Remove unnecessary calls that apply icon color tint.

- `mTitleIcon.setBackgroundTintList` is a no-op since mTitleIcon doesn't have a background, the actual color tint is performed by `mTitleIcon.setImageTintList`.
- `MediaSwitchingCongtroller#setColorFilter` was added to add a color tint to the device icon, but it's useless now because `mTitleIcon.setImageTintList` does the exact same thing.

Bug: 387570618
Flag: EXEMPT bugfix
Test: Verified on a physical device.
Change-Id: I81d934e0c7ee9c0dd227f017e942917ace1edc0a