Add IProducerListener::onBufferAttached

Add a new callback to IProducerListener for buffer being attached to the
consumer.
BYPASS_IGBP_IGBC_API_REASON=approved new code in libgui

Bug: 353202582
Flag: com.android.graphics.libgui.flags.bq_consumer_attach_callback
(cherry picked from https://android-review.googlesource.com/q/commit:6d223cbd07f0582ac99e4b607f6983284638aa0b)
Merged-In: I21f9d4925ab6c8985ab349514bc0198e61d1de23
Change-Id: I21f9d4925ab6c8985ab349514bc0198e61d1de23