[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 a1da43ab5aa138e4f34b3950b71af68f9ef40d04..cd69eaa2a269efdb822be69dc46941a379e86241 100644
--- a/build/config/android/rules.gni
+++ b/build/config/android/rules.gni
@@ -1333,6 +1333,17 @@ 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 = []
@@ -1418,9 +1429,9 @@ 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,