tools: fix source heap profile script
tools: fix source heap profile script

aosp/2218801 changed the script directly: port the change over to the
.py file.

Change-Id: I672b56444ea378fd4dad3abac431fcc2018d2a70
google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto