libyuv: Add got_revision property mapping.

scripts/slave/recipes/libyuv/libyuv.expected/client_libyuv_android_clang_debug.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_MODULE[depot_tools::bot_update]/resources/bot_update.py",
       "--master",
       "client.libyuv",
       "--builder",
       "Android Clang Debug",
       "--slave",
       "slavename",
       "--spec",
       "cache_dir = '[GIT_CACHE]'\nsolutions = [{'custom_vars': {'root_dir': 'src'}, 'deps_file': 'DEPS', 'managed': True, 'name': 'src', 'url': 'https://chromium.googlesource.com/libyuv/libyuv'}]\ntarget_os = ['android']",
       "--root",
       "src",
       "--revision_mapping_file",
-      "{}",
+      "{\"src\": \"got_revision\"}",
       "--git-cache-dir",
       "[GIT_CACHE]",
       "--output_json",
       "/path/to/tmp/json",
       "--revision",
       "src@12345",
       "--force",
       "--output_manifest"
     ],
     "env": {
       "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]"
     },
     "name": "bot_update",
     "~followup_annotations": [
       "@@@STEP_TEXT@Some step text@@@",
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"did_run\": true, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"fixed_revisions\": {@@@",
       "@@@STEP_LOG_LINE@json.output@    \"src\": \"12345\"@@@",
       "@@@STEP_LOG_LINE@json.output@  }, @@@",
-      "@@@STEP_LOG_LINE@json.output@  \"manifest\": {}, @@@",
+      "@@@STEP_LOG_LINE@json.output@  \"manifest\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"src\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@      \"repository\": \"https://fake.org/src.git\", @@@",
+      "@@@STEP_LOG_LINE@json.output@      \"revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\"@@@",
+      "@@@STEP_LOG_LINE@json.output@    }@@@",
+      "@@@STEP_LOG_LINE@json.output@  }, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"patch_failure\": false, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"patch_root\": \"src\", @@@",
-      "@@@STEP_LOG_LINE@json.output@  \"properties\": {}, @@@",
+      "@@@STEP_LOG_LINE@json.output@  \"properties\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", @@@",
+      "@@@STEP_LOG_LINE@json.output@    \"got_revision_cp\": \"refs/heads/master@{#170242}\"@@@",
+      "@@@STEP_LOG_LINE@json.output@  }, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"root\": \"src\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"step_text\": \"Some step text\"@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
-      "@@@STEP_LOG_END@json.output@@@"
+      "@@@STEP_LOG_END@json.output@@@",
+      "@@@SET_BUILD_PROPERTY@got_revision@\"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\"@@@",
+      "@@@SET_BUILD_PROPERTY@got_revision_cp@\"refs/heads/master@{#170242}\"@@@"
     ]
   },
   {
     "cmd": [],
     "name": "ensure_goma"
   },
   {
     "cmd": [
       "python",
       "-u",
@@ skipping 129 matching lines @@
       "@@@STEP_LOG_LINE@json.output (invalid)@null@@@",
       "@@@STEP_LOG_END@json.output (invalid)@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]