Upstream changes to HttpUrlRequest for querying response headers and closing ReadableByteChannel.

components/cronet/android/java/src/org/chromium/net/HttpUrlRequest.java

Index: components/cronet/android/java/src/org/chromium/net/HttpUrlRequest.java
diff --git a/components/cronet/android/java/src/org/chromium/net/HttpUrlRequest.java b/components/cronet/android/java/src/org/chromium/net/HttpUrlRequest.java
index 71901a822c3bf316d418bd5fa503934338df587e..cefb95ea65cb9aa5f3daad34d40fdbe83d4bc88f 100644
--- a/components/cronet/android/java/src/org/chromium/net/HttpUrlRequest.java
+++ b/components/cronet/android/java/src/org/chromium/net/HttpUrlRequest.java
@@ -58,6 +58,9 @@ public interface HttpUrlRequest {
     /**
      * Sets a readable byte channel to upload as part of a POST request.
      *
+     * <p>Once {@link #start()} is called, this channel is guaranteed to be
+     * closed, either when the upload completes, or when it is canceled.
+     *
      * @param contentType MIME type of the post content or null if this is not a
      *            POST.
      * @param channel The channel to read to read upload data from if this is a
@@ -113,6 +116,13 @@ public interface HttpUrlRequest {
     int getHttpStatusCode();
 
     /**
+     * Returns the response header value for the given name or {@code null} if
+     * not found.
+     */
+    String getHeader(String name);
+
+
+    /**
      * Returns the exception that occurred while executing the request of null
      * if the request was successful.
      */