Switch to Cronet 56_0_2924_0

This is the second CL in the 3 CL process to switch Cronet versions.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=140074017

extensions/cronet/src/androidTest/java/com/google/android/exoplayer2/ext/cronet/CronetDataSourceTest.java

@@ -60,6 +60,7 @@ import org.chromium.net.CronetEngine;
 import org.chromium.net.UrlRequest;
 import org.chromium.net.UrlRequestException;
 import org.chromium.net.UrlResponseInfo;
+import org.chromium.net.impl.UrlResponseInfoImpl;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -138,7 +139,7 @@ public final class CronetDataSourceTest {
   private UrlResponseInfo createUrlResponseInfo(int statusCode) {
     ArrayList<Map.Entry<String, String>> responseHeaderList = new ArrayList<>();
     responseHeaderList.addAll(testResponseHeader.entrySet());
-    return new UrlResponseInfo(
+    return new UrlResponseInfoImpl(
         Collections.singletonList(TEST_URL),
         statusCode,
         null, // httpStatusText