[Cronet] Make some test infrastructure public rather than package-private.

There's no reason to have it package-private, and this prevents sharing with
tests in other packages (e.g. org.chromium.net.urlconnection).

BUG=629299
R=xunjieli
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.android:android_cronet_tester

Review-Url: https://codereview.chromium.org/2568213002
Cr-Commit-Position: refs/heads/master@{#437921}

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

@@ -152,7 +152,7 @@ public class CronetTestBase extends AndroidTestCase {
         }
     }
 
-    void assertResponseEquals(UrlResponseInfo expected, UrlResponseInfo actual) {
+    public void assertResponseEquals(UrlResponseInfo expected, UrlResponseInfo actual) {
         assertEquals(expected.getAllHeaders(), actual.getAllHeaders());
         assertEquals(expected.getAllHeadersAsList(), actual.getAllHeadersAsList());
         assertEquals(expected.getHttpStatusCode(), actual.getHttpStatusCode());
@@ -168,7 +168,7 @@ public class CronetTestBase extends AndroidTestCase {
         }
     }
 
-    static void assertContains(String expectedSubstring, String actualString) {
+    public static void assertContains(String expectedSubstring, String actualString) {
         assertNotNull(actualString);
         if (!actualString.contains(expectedSubstring)) {
             fail("String [" + actualString + "] doesn't contain substring [" + expectedSubstring

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

@@ -27,7 +27,7 @@ import java.util.concurrent.TimeUnit;
  * method to block thread until the request completes on another thread.
  * Allows to cancel, block request or throw an exception from an arbitrary step.
  */
-class TestUrlRequestCallback extends UrlRequest.Callback {
+public class TestUrlRequestCallback extends UrlRequest.Callback {
     public ArrayList<UrlResponseInfo> mRedirectResponseInfoList = new ArrayList<UrlResponseInfo>();
     public ArrayList<String> mRedirectUrlList = new ArrayList<String>();
     public UrlResponseInfo mResponseInfo;