Simplify config for Clang ToT builders.

scripts/slave/recipes/chromium.expected/full_chromium_fyi_ClangToTAndroidASan_tester.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/bot_update.py",
       "--master",
       "chromium.fyi",
       "--builder",
       "ClangToTAndroidASan tester",
@@ skipping 80 matching lines @@
   {
     "cmd": [
       "python",
       "-u",
       "[DEPOT_TOOLS]/gclient.py",
       "runhooks"
     ],
     "cwd": "[SLAVE_BUILD]",
     "env": {
       "GYP_CROSSCOMPILE": "1",
-      "GYP_DEFINES": "OS=android asan=1 clang=1 component=shared_library fastbuild=1 target_arch=ia32",
+      "GYP_DEFINES": "OS=android asan=1 clang=1 clang_use_chrome_plugins=0 component=shared_library fastbuild=1 target_arch=ia32",
       "LLVM_FORCE_HEAD_REVISION": "YES",
       "PATH": "[SLAVE_BUILD]/src/third_party/android_tools/sdk/platform-tools:[SLAVE_BUILD]/src/build/android:%(PATH)s"
     },
     "name": "gclient runhooks"
   },
   {
     "cmd": [
       "python",
       "-u",
       "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
@@ skipping 545 matching lines @@
       "@@@STEP_LOG_LINE@python.inline@  os.remove(report)@@@",
       "@@@STEP_LOG_END@python.inline@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]