Update the script to generate icu4c/source/test/testdata/out

It was generated manually, e.g. in https://r.android.com/1547601,
but now generated by updateicudata.py.

Test: rm -r icu4c/source/test/testdata/out && ./tools/updateicudata.py
Change-Id: I0e9cec7cf4f6b01b2ef22d04b712f9c98eb6bea4
diff --git a/tools/icuutil.py b/tools/icuutil.py
index b9cf35a..f44a086 100644
--- a/tools/icuutil.py
+++ b/tools/icuutil.py
@@ -142,6 +142,9 @@
   # Generate the ICU4J .jar files
   subprocess.check_call(['make', '-j32', 'icu4j-data'])
 
+  # Generate the test data in icu4c/source/test/testdata/out
+  subprocess.check_call(['make', '-j32', 'tests'])
+
   # Copy the ICU4J .jar files to their ultimate destination.
   icu_jar_data_dir = '%s/main/shared/data' % icu4jDir()
   jarfiles = glob.glob('data/out/icu4j/*.jar')
@@ -156,6 +159,12 @@
       print('Copying %s to %s ...' % (jarfile, icu_jar_data_dir))
       shutil.copy(jarfile, icu_jar_data_dir)
 
+  testdata_out_dir = '%s/test/testdata/out' % icu4cDir()
+  print('Copying test data to %s ' % testdata_out_dir)
+  if os.path.exists(testdata_out_dir):
+    shutil.rmtree(testdata_out_dir)
+  shutil.copytree('test/testdata/out', testdata_out_dir)
+
   # Switch back to the original working cwd.
   os.chdir(original_working_dir)