[Android] Use mb on chromium.linux and tryserver.chromium.android.

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

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_MODULE[depot_tools::bot_update]/resources/bot_update.py",
       "--master",
       "chromium.linux",
       "--builder",
       "Android Builder (dbg)",
@@ skipping 115 matching lines @@
   },
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[depot_tools]/gclient.py",
       "runhooks"
     ],
     "cwd": "[SLAVE_BUILD]",
     "env": {
+      "GYP_CHROMIUM_NO_ACTION": "1",
       "GYP_CROSSCOMPILE": "1",
       "GYP_DEFINES": "OS=android component=static_library fastbuild=1 ffmpeg_branding=Chrome gomadir='[SLAVE_BUILD]/src/build/goma/client' proprietary_codecs=1 target_arch=arm test_isolation_mode=prepare use_goma=1",
       "PATH": "[SLAVE_BUILD]/src/third_party/android_tools/sdk/platform-tools:[SLAVE_BUILD]/src/build/android:%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]"
     },
     "name": "gclient runhooks"
   },
   {
     "cmd": [
       "python",
       "-u",
@@ skipping 99 matching lines @@
       "[SLAVE_BUILD]/src/out/Debug",
       "--clean-isolated-files"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "clean isolated files"
   },
   {
     "cmd": [
       "python",
       "-u",
+      "[SLAVE_BUILD]/src/tools/mb/mb.py",
+      "gen",
+      "-m",
+      "chromium.linux",
+      "-b",
+      "Android Builder (dbg)",
+      "--config-file",
+      "[SLAVE_BUILD]/src/tools/mb/mb_config.pyl",
+      "--goma-dir",
+      "[BUILD]/goma",
+      "--swarming-targets-file",
+      "browser_tests_apk\n",
+      "//out/Debug"
+    ],
+    "cwd": "[SLAVE_BUILD]",
+    "name": "generate_build_files",
+    "~followup_annotations": [
+      "@@@STEP_LOG_LINE@swarming-targets-file.txt@browser_tests_apk@@@",
+      "@@@STEP_LOG_END@swarming-targets-file.txt@@@"
+    ]
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
       "RECIPE_PACKAGE_REPO[build]/scripts/slave/compile.py",
       "--target",
       "Debug",
       "--src-dir",
       "[SLAVE_BUILD]/src",
       "--build-tool",
       "ninja",
       "--compiler",
       "goma",
       "--goma-jsonstatus",
@@ skipping 104 matching lines @@
     "~followup_annotations": [
       "@@@STEP_TEXT@Android Tests (dbg)@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]