Do not dump maps/memory/code of sibling threads. DO NOT MERGE

Modifies the code so that if the unwind fails, the code still prints
as much data as possible.

Also, for sibling threads, skip printing the maps and memory/code
since it's not likely to be very relevant.

Fix a few cases where extra space is at the end of lines.

Fix an inverted if statement that was checking the wrong condition.

Bug: 18816322
Bug: 20829534

(cherry picked from ab9e7dce)

Change-Id: If2d3a734724c23df4192f4dfc6bd69d6729fbc8d