[Cronet] add a test assertion in UploadDataProvidersTest.java

components/cronet/android/test/javatests/src/org/chromium/net/UploadDataProvidersTest.java

Index: components/cronet/android/test/javatests/src/org/chromium/net/UploadDataProvidersTest.java
diff --git a/components/cronet/android/test/javatests/src/org/chromium/net/UploadDataProvidersTest.java b/components/cronet/android/test/javatests/src/org/chromium/net/UploadDataProvidersTest.java
index 1d6d923f1b4aae2293eda79c551de6732c5a3286..fa7a540b1c79845c268d99ea43bf18d4f4dc3f4d 100644
--- a/components/cronet/android/test/javatests/src/org/chromium/net/UploadDataProvidersTest.java
+++ b/components/cronet/android/test/javatests/src/org/chromium/net/UploadDataProvidersTest.java
@@ -224,6 +224,7 @@ public class UploadDataProvidersTest extends CronetTestBase {
         System.arraycopy(uploadData, 0, uploadDataWithPadding, offset, uploadData.length);
         UploadDataProvider dataProvider =
                 UploadDataProviders.create(uploadDataWithPadding, offset, uploadData.length);
+        assertEquals(uploadData.length, dataProvider.getLength());
         builder.setUploadDataProvider(dataProvider, callback.getExecutor());
         UrlRequest urlRequest = builder.build();
         urlRequest.start();