libaddressinput: Add fallback data for US address validation.

third_party/libaddressinput/chromium/cpp/test/retriever_test.cc

Index: third_party/libaddressinput/chromium/cpp/test/retriever_test.cc
diff --git a/third_party/libaddressinput/chromium/cpp/test/retriever_test.cc b/third_party/libaddressinput/chromium/cpp/test/retriever_test.cc
index 13e9ad1c22945b466630dcf55bc6e1bb43bbcb55..8d8e04039d27c35ed2ffd465a80c0496b1ebae88 100644
--- a/third_party/libaddressinput/chromium/cpp/test/retriever_test.cc
+++ b/third_party/libaddressinput/chromium/cpp/test/retriever_test.cc
@@ -134,6 +134,19 @@ TEST_F(RetrieverTest, FaultyDownloader) {
   EXPECT_TRUE(data_.empty());
 }
 
+TEST_F(RetrieverTest, FaultyDownloaderFallback) {
+  Retriever bad_retriever(FakeDownloader::kFakeDataUrl,
+                          scoped_ptr<Downloader>(new FaultyDownloader),
+                          scoped_ptr<Storage>(new FakeStorage));
+  const char kFallbackDataKey[] = "data/US";
+  bad_retriever.Retrieve(kFallbackDataKey, BuildCallback());
+
+  EXPECT_TRUE(success_);
+  EXPECT_EQ(kFallbackDataKey, key_);
+  EXPECT_FALSE(data_.empty());
+  EXPECT_NE(kEmptyData, data_);
+}
+
 // The downloader that doesn't get back to you.
 class HangingDownloader : public Downloader {
  public: