WebRTC: Remove get_version step from WebRTC bots.

scripts/slave/recipes/webrtc/standalone.expected/tryserver_webrtc_android_arm64_rel.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_MODULE[depot_tools::bot_update]/resources/bot_update.py",
       "--master",
       "tryserver.webrtc",
       "--builder",
       "android_arm64_rel",
@@ skipping 692 matching lines @@
     ],
     "env": {
       "CHROMIUM_OUTPUT_DIR": "[SLAVE_BUILD]/src/out/Release",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json",
       "PATH": "[SLAVE_BUILD]/src/third_party/android_tools/sdk/platform-tools:[SLAVE_BUILD]/src/build/android:%(PATH)s"
     },
     "name": "stack_tool_with_logcat_dump"
   },
   {
     "cmd": [
-      "python",
-      "-u",
-      "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
-      "[SLAVE_BUILD]/src/chrome/VERSION",
-      "/path/to/tmp/"
-    ],
-    "name": "get version"
-  },
-  {
-    "cmd": [
       "[SLAVE_BUILD]/src/build/android/tombstones.py",
       "-a",
       "-s",
-      "-w"
+      "-w",
+      "--adb-path",
+      "[SLAVE_BUILD]/src/third_party/android_tools/sdk/platform-tools/adb"
     ],
     "env": {
       "CHROMIUM_OUTPUT_DIR": "[SLAVE_BUILD]/src/out/Release",
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json",
       "PATH": "[SLAVE_BUILD]/src/third_party/android_tools/sdk/platform-tools:[SLAVE_BUILD]/src/build/android:%(PATH)s"
     },
     "name": "stack_tool_for_tombstones"
   },
   {
     "cmd": [
@@ skipping 13 matching lines @@
       "@@@STEP_LOG_LINE@python.inline@  os.remove(report)@@@",
       "@@@STEP_LOG_END@python.inline@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]