Removes dont_embed_build_metadata in preparation for its removal.

scripts/slave/recipes/deterministic_build.expected/full_chromium_swarm_mac_deterministic.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/cleanup_temp.py"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "cleanup_temp"
   },
@@ skipping 97 matching lines @@
   },
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE[depot_tools]/gclient.py",
       "runhooks"
     ],
     "cwd": "[SLAVE_BUILD]",
     "env": {
-      "GYP_DEFINES": "clang=1 component=static_library dont_embed_build_metadata=1 gomadir='[BUILD]/goma' target_arch=ia32 test_isolation_mode=prepare use_goma=1",
+      "GYP_DEFINES": "clang=1 component=static_library gomadir='[BUILD]/goma' target_arch=ia32 test_isolation_mode=prepare use_goma=1",
       "PATH": "%(PATH)s:RECIPE_PACKAGE[depot_tools]"
     },
     "name": "gclient runhooks"
   },
   {
     "allow_subannotations": true,
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/clang_revision.py",
@@ skipping 115 matching lines @@
   },
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE[depot_tools]/gclient.py",
       "runhooks"
     ],
     "cwd": "[SLAVE_BUILD]",
     "env": {
-      "GYP_DEFINES": "clang=1 component=static_library dont_embed_build_metadata=1 gomadir='[BUILD]/goma' target_arch=ia32 test_isolation_mode=prepare use_goma=1",
+      "GYP_DEFINES": "clang=1 component=static_library gomadir='[BUILD]/goma' target_arch=ia32 test_isolation_mode=prepare use_goma=1",
       "PATH": "%(PATH)s:RECIPE_PACKAGE[depot_tools]"
     },
     "name": "gclient runhooks (2)"
   },
   {
     "allow_subannotations": true,
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/clang_revision.py",
@@ skipping 123 matching lines @@
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "compare_build_artifacts"
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]