Update from https://crrev.com/317530

base/android/jni_generator/jni_generator_tests.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Tests for jni_generator.py.
 
 This test suite contains various tests for the JNI generator.
 It exercises the low-level parser all the way up to the
 code generator and ensures the output matches a golden
@@ skipping 25 matching lines @@
     self.namespace = None
     self.script_name = SCRIPT_NAME
     self.includes = INCLUDES
     self.pure_native_methods = False
     self.ptr_type = 'long'
     self.jni_init_native_name = None
     self.eager_called_by_natives = False
     self.cpp = 'cpp'
     self.javap = 'javap'
     self.native_exports = False
+    self.native_exports_optional = False
 
 class TestGenerator(unittest.TestCase):
   def assertObjEquals(self, first, second):
     dict_first = first.__dict__
     dict_second = second.__dict__
     self.assertEquals(dict_first.keys(), dict_second.keys())
     for key, value in dict_first.iteritems():
       if (type(value) is list and len(value) and
           isinstance(type(value[0]), object)):
         self.assertListEquals(value, second.__getattribute__(key))
@@ skipping 956 matching lines @@
         private static String testStaticMethodWithNoParam();
     }
     """
     options = TestOptions()
     options.jni_init_native_name = 'nativeInitNativeClass'
     options.eager_called_by_natives = True
     jni_from_java = jni_generator.JNIFromJavaSource(
         test_data, 'org/chromium/example/jni_generator/Test', options)
     self.assertGoldenTextEquals(jni_from_java.GetContent())
 
-  def testNativeExportsOption(self):
+  def runNativeExportsOption(self, optional):
     test_data = """
     package org.chromium.example.jni_generator;
 
     /** The pointer to the native Test. */
     long nativeTest;
 
     class Test {
         private static native boolean nativeInitNativeClass();
         private static native int nativeStaticMethod(long nativeTest, int arg1);
         private native int nativeMethod(long nativeTest, int arg1);
@@ skipping 14 matching lines @@
         }
         class MyOtherInnerClass {
           @NativeCall("MyOtherInnerClass")
           private native int nativeInit();
         }
     }
     """
     options = TestOptions()
     options.jni_init_native_name = 'nativeInitNativeClass'
     options.native_exports = True
+    options.native_exports_optional = optional
     jni_from_java = jni_generator.JNIFromJavaSource(
         test_data, 'org/chromium/example/jni_generator/SampleForTests', options)
-    self.assertGoldenTextEquals(jni_from_java.GetContent())
+    return jni_from_java.GetContent()
+
+  def testNativeExportsOption(self):
+    content = self.runNativeExportsOption(False)
+    self.assertGoldenTextEquals(content)
+
+  def testNativeExportsOptionalOption(self):
+    content = self.runNativeExportsOption(True)
+    self.assertGoldenTextEquals(content)
 
   def testOuterInnerRaises(self):
     test_data = """
     package org.chromium.media;
 
     @CalledByNative
     static int getCaptureFormatWidth(VideoCapture.CaptureFormat format) {
         return format.getWidth();
     }
     """
@@ skipping 63 matching lines @@
     }
     """
     jni_from_java = jni_generator.JNIFromJavaSource(test_data,
                                                     'org/chromium/foo/Foo',
                                                     TestOptions())
     self.assertGoldenTextEquals(jni_from_java.GetContent())
 
 
 if __name__ == '__main__':
   unittest.main()