Add self tests for gyp_to_android.

tools/tests/run_all.py

Index: tools/tests/run_all.py
diff --git a/tools/tests/run_all.py b/tools/tests/run_all.py
index 84886f758f4397d7c583affb9579dafb83e05213..e0856735e72d66082bd9d1cb5ee4eeb9c271c3ca 100755
--- a/tools/tests/run_all.py
+++ b/tools/tests/run_all.py
@@ -12,11 +12,13 @@ of them fail.
 
 import render_pictures_test
 import skimage_self_test
+import gyp_to_android_tests
 
 def main():
   """Run all self-tests, raising an exception if any of them fail."""
   render_pictures_test.main()
   skimage_self_test.main()
+  gyp_to_android_tests.main()
 
 if __name__ == '__main__':
   main()