Guard against possible exception when tracing

Trace.beginSection() throws an IllegalArgumentException if section name
is longer than 127 chars. Therefore, it shouldn't be used anytime a
string name is generated at runtime. Instead, replace with equivalent
call to Trace.traceBegin().

Also, guard against StringBuilder GC garbage while tracing.

Test: manual
Bug: 257075630
Change-Id: Ia3477dc98b7d87f6fcd0c4f2e0aaad976f2203a2