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

base/base.gyp

Index: base/base.gyp
diff --git a/base/base.gyp b/base/base.gyp
index 2f8738ebb72ecfcd4123e2b7e454ff5f58c07475..1107de0af75fa5b060c981a9f7504af3f6b2b4d3 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -1476,6 +1476,19 @@
           'includes': ['../build/android/java_cpp_template.gypi'],
         },
         {
+          # GN: //base:base_native_test_libraries_gen
+          'target_name': 'base_native_test_libraries_gen',
+          'type': 'none',
+          'sources': [
+            'test/android/java/templates/NativeTestLibraries.template',
+          ],
+          'variables': {
+            'package_name': 'org/chromium/base/test/library_loader',
+            'template_deps': [],
+          },
+          'includes': [ '../build/android/java_cpp_template.gypi' ],
+        },
+        {
           # GN: //base:base_android_java_enums_srcjar
           'target_name': 'base_java_library_process_type',
           'type': 'none',
@@ -1549,9 +1562,11 @@
           'type': 'none',
           'dependencies': [
             'base_java',
+            'base_native_test_libraries_gen',
             '../testing/android/on_device_instrumentation.gyp:reporter_java',
           ],
           'variables': {
+            'jar_excluded_classes': [ '*/NativeTestLibraries.class' ],
             'java_in_dir': '../base/test/android/javatests',
           },
           'includes': [ '../build/java.gypi' ],