Fix event_log_visualizer help text and default profile.
Fix event_log_visualizer help text and default profile.

Bug: webrtc:10623
Change-Id: I628881039200bdeef5469d913c085ef50d3352c4
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/141868
Reviewed-by: Sebastian Jansson <c24d1bc144eb7c11e553f59153fa17dba85ca83e@webrtc.org>
Commit-Queue: Björn Terelius <efeae16329b3cb4ac5daf80d4bfda3344c027db3@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#28299}

TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc