cronet: delete option to disable cronet in tm-mainline-prod

With the release cut of the July train and the recent automerger
cutover, tm-mainline-prod is now officially an abandoned branch.

This change deletes (most) infrastructure that was put in place to
disable cronet on tm-mainline-prod.

Test: builds
Change-Id: I078f2114b736a634f08d8f704c19beb2224ef645
diff --git a/Cronet/tests/mts/Android.bp b/Cronet/tests/mts/Android.bp
index ecf4b7f..93564e4 100644
--- a/Cronet/tests/mts/Android.bp
+++ b/Cronet/tests/mts/Android.bp
@@ -19,7 +19,6 @@
 
 java_genrule {
     name: "net-http-test-jarjar-rules",
-    defaults: ["CronetTestJavaDefaults"],
     tool_files: [
         ":NetHttpTestsLibPreJarJar{.jar}",
         "jarjar_excludes.txt",
@@ -37,7 +36,6 @@
 
 android_library {
     name: "NetHttpTestsLibPreJarJar",
-    defaults: ["CronetTestJavaDefaults"],
     srcs: [":cronet_aml_javatests_sources"],
     sdk_version: "module_current",
     min_sdk_version: "30",
@@ -46,6 +44,7 @@
         "androidx.test.ext.junit",
         "androidx.test.rules",
         "junit",
+        "truth",
     ],
     libs: [
         "android.test.base",
@@ -59,7 +58,6 @@
 android_test {
      name: "NetHttpTests",
      defaults: [
-        "CronetTestJavaDefaults",
         "mts-target-sdk-version-current",
      ],
      static_libs: ["NetHttpTestsLibPreJarJar"],