(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/pc/jsep_session_description_unittest.cc b/pc/jsep_session_description_unittest.cc
index 04577e2..2eb1db0 100644
--- a/pc/jsep_session_description_unittest.cc
+++ b/pc/jsep_session_description_unittest.cc
@@ -18,18 +18,18 @@
 #include "absl/memory/memory.h"
 #include "api/candidate.h"
 #include "api/jsep.h"
-#include "api/jsepicecandidate.h"
-#include "api/jsepsessiondescription.h"
+#include "api/jsep_ice_candidate.h"
+#include "api/jsep_session_description.h"
 #include "media/base/codec.h"
-#include "p2p/base/p2pconstants.h"
+#include "p2p/base/p2p_constants.h"
 #include "p2p/base/port.h"
-#include "p2p/base/transportdescription.h"
-#include "p2p/base/transportinfo.h"
-#include "pc/sessiondescription.h"
-#include "pc/webrtcsdp.h"
+#include "p2p/base/transport_description.h"
+#include "p2p/base/transport_info.h"
+#include "pc/session_description.h"
+#include "pc/webrtc_sdp.h"
 #include "rtc_base/helpers.h"
-#include "rtc_base/socketaddress.h"
-#include "rtc_base/stringencode.h"
+#include "rtc_base/socket_address.h"
+#include "rtc_base/string_encode.h"
 #include "test/gtest.h"
 
 using cricket::MediaProtocolType;