[Android] Add ChromiumNetTestSupport.apk for the java EmbeddedTestServer.

build/config/android/rules.gni

Index: build/config/android/rules.gni
diff --git a/build/config/android/rules.gni b/build/config/android/rules.gni
index e65607045caf93c1c238dda2cd3d80c8f40de0c6..c57f41ad9de244f79cbb5db5752bcb00c1f6571b 100644
--- a/build/config/android/rules.gni
+++ b/build/config/android/rules.gni
@@ -1347,6 +1347,17 @@ template("android_apk") {
     if (defined(invoker.native_lib_version_arg)) {
       _native_lib_version_arg = invoker.native_lib_version_arg
     }
+
+    _native_libraries_template =
+        "//base/android/java/templates/NativeLibraries.template"
+    if (defined(invoker.native_libraries_template)) {
+      _native_libraries_template = invoker.native_libraries_template
+    }
+
+    _native_libraries_package_name = "org/chromium/base/library_loader"
+    if (defined(invoker.native_libraries_package_name)) {
+      _native_libraries_package_name = invoker.native_libraries_package_name
+    }
   }
 
   _android_manifest_deps = []
@@ -1432,9 +1443,9 @@ template("android_apk") {
     }
 
     java_cpp_template("${_template_name}__native_libraries_java") {
-      package_name = "org/chromium/base/library_loader"
+      package_name = _native_libraries_package_name
       sources = [
-        "//base/android/java/templates/NativeLibraries.template",
+        _native_libraries_template,
       ]
       inputs = [
         _build_config,
@@ -1875,6 +1886,7 @@ template("instrumentation_test_apk") {
       "//tools/android/forwarder2",
       "//tools/android/md5sum",
     ]
+
     run_findbugs = false
   }