perf tools: Handle PERF_RECORD_HEADER_EVENT_TYPE properly

We removed event types from data file in following commits:

  6065210 perf tools: Remove event types framework completely
  44b3c57 perf tools: Remove event types from perf data file

We no longer need this information, because we can get it directly from
tracepoints.

But we still need to handle PERF_RECORD_HEADER_EVENT_TYPE event for the
sake of old perf data files created in pipe mode like:

  $ perf.3.4 record -o - foo >perf.data
  $ perf.312 report -i - < perf.data

Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1391524668-12546-1-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 0b39a48..5da6ce7 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1008,6 +1008,12 @@
 		if (err == 0)
 			perf_session__set_id_hdr_size(session);
 		return err;
+	case PERF_RECORD_HEADER_EVENT_TYPE:
+		/*
+		 * Depreceated, but we need to handle it for sake
+		 * of old data files create in pipe mode.
+		 */
+		return 0;
 	case PERF_RECORD_HEADER_TRACING_DATA:
 		/* setup for reading amidst mmap */
 		lseek(fd, file_offset, SEEK_SET);