trace_to_text: add event counts for each type of ftrace event am: 13c6177aa2
trace_to_text: add event counts for each type of ftrace event
am: 13c6177aa2

Change-Id: I52ccd620d401772b995020d2c75db46e29be462f

google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto