(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}

examples/androidnativeapi/BUILD.gn

@@ -37,8 +37,8 @@ if (is_android) {
   rtc_shared_library("examples_androidnativeapi_jni") {
     testonly = true
     sources = [
-      "jni/androidcallclient.cc",
-      "jni/androidcallclient.h",
+      "jni/android_call_client.cc",
+      "jni/android_call_client.h",
       "jni/onload.cc",
     ]