Merge "Document that some Telecom broadcast and extra keys are dead-ends."...
Merge "Document that some Telecom broadcast and extra keys are dead-ends." into rvc-dev am: f7643e91 am: df77eb4a am: 1e4b7bff am: b638c42d
Change-Id: Iacf1c3870270b0ec7a4f853e1ff66efbbba41c09