Remove support for old naming convention for EarlGrey tests on iOS.

ios/build/tools/convert_gn_xcodeproj.py

Index: ios/build/tools/convert_gn_xcodeproj.py
diff --git a/ios/build/tools/convert_gn_xcodeproj.py b/ios/build/tools/convert_gn_xcodeproj.py
index a5d6209438c9bbc721e25c73d9109add56cd46c0..668104f6e3b2d9f4a4445949cc90420924a68a50 100755
--- a/ios/build/tools/convert_gn_xcodeproj.py
+++ b/ios/build/tools/convert_gn_xcodeproj.py
@@ -122,12 +122,8 @@ def UpdateProductsProject(file_input, file_output, configurations):
       for config_name in configuration_list['buildConfigurations']:
         config = project.objects[config_name]
         if not config['buildSettings'].get('BUNDLE_LOADER'):
-          if value['name'].endswith('_module'):
-            host_name = value['name'][:-len('_module')]
-          else:
-            # TODO(crbug.com/662404): remove once the targets have been renamed
-            # to use the new naming convention.
-            host_name = value['name'] + '_host'
+          assert value['name'].endswith('_module')
+          host_name = value['name'][:-len('_module')]
           config['buildSettings']['BUNDLE_LOADER'] = '$(TEST_HOST)'
           config['buildSettings']['TEST_HOST'] = \
               '${BUILT_PRODUCTS_DIR}/%s.app/%s' % (host_name, host_name)