(4) Rename files to snake_case: update BUILD.gn, include paths, header guards, and DEPS entries

Mechanically generated by running this command:

tools_webrtc/do-renames.sh update all-renames.txt && git cl format

Then manually updating:

tools_webrtc/sanitizers/tsan_suppressions_webrtc.cc

Bug: webrtc:10159
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Change-Id: I54824cd91dada8fc3ee3d098f971bc319d477833
Reviewed-on: https://webrtc-review.googlesource.com/c/115653
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26226}
diff --git a/test/scenario/network_node.h b/test/scenario/network_node.h
index 190ecb2..cce1dd9 100644
--- a/test/scenario/network_node.h
+++ b/test/scenario/network_node.h
@@ -20,8 +20,8 @@
 #include "api/units/timestamp.h"
 #include "call/call.h"
 #include "call/simulated_network.h"
-#include "rtc_base/constructormagic.h"
-#include "rtc_base/copyonwritebuffer.h"
+#include "rtc_base/constructor_magic.h"
+#include "rtc_base/copy_on_write_buffer.h"
 #include "test/scenario/column_printer.h"
 #include "test/scenario/network/network_emulation.h"
 #include "test/scenario/scenario_config.h"