Fix Foreground-to-Background color switching of vector objects

If the fg-bg color was swapped rapidly enough, the resulting shape would often have the same color (rather than it being swapped).

The reason for this being resourceManager would send us signal to change both fg and bg, but if the delay between them is less than colorChangedCompressor's timeout, the latter signal would be ignored. Which would prevent the swapping from happening. The proper solutions seem to be to either have a compressor at the source (which there does seem to be) or have separate channel (ie different timers) for different resources (bg, fg and gradient in this case).

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Test Plan

BUG:458913

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