Revert "docs: Revised descriptions of binding and connecting to services."

This reverts commit 34acbc9b.

Reason for revert: You must always call unbindService() after
bindService(), regardless of the return value for bindService();
see https://groups.google.com/a/google.com/g/android-chatty-eng/c/reDuVZl9Tcs/m/ux52rVvoAQAJ

Bug: 37092557

Test: m ds-docs-java

Change-Id: Ie4461b9a3b64ed3fb6f32e3cb71b57976e8da90f