Also, as evidence that the picture present on the launcher icon affects the chameleonic effect as well, observe these comparison screenshots using the FS Icons Ubuntu icon theme (development version r43) between when the Trash is empty and when it is not (note the reddish hue in the second screenshot, when it is supposed to be purple). Note that between them only the icon changed; no other settings were altered.
Also, as evidence that the picture present on the launcher icon affects the chameleonic effect as well, observe these comparison screenshots using the FS Icons Ubuntu icon theme (development version r43) between when the Trash is empty and when it is not (note the reddish hue in the second screenshot, when it is supposed to be purple). Note that between them only the icon changed; no other settings were altered.