Support setReadTimeout in CronetHttpURLConnection

components/cronet/android/java/src/org/chromium/net/urlconnection/CronetHttpURLConnection.java

Index: components/cronet/android/java/src/org/chromium/net/urlconnection/CronetHttpURLConnection.java
diff --git a/components/cronet/android/java/src/org/chromium/net/urlconnection/CronetHttpURLConnection.java b/components/cronet/android/java/src/org/chromium/net/urlconnection/CronetHttpURLConnection.java
index 1575a696d504f4efa0b8813d9a2f5ffd485d9304..6b421d7de42d5a34a217bb94702406018869ade2 100644
--- a/components/cronet/android/java/src/org/chromium/net/urlconnection/CronetHttpURLConnection.java
+++ b/components/cronet/android/java/src/org/chromium/net/urlconnection/CronetHttpURLConnection.java
@@ -405,7 +405,7 @@ public class CronetHttpURLConnection extends HttpURLConnection {
      */
     void getMoreData(ByteBuffer byteBuffer) throws IOException {
         mRequest.read(byteBuffer);
-        mMessageLoop.loop();
+        mMessageLoop.loop(getReadTimeout());

[jdcormie, 2016/05/17 17:48:34]

MessageLoop.loop(int timeout) appears to pull and run tasks from the queue until
it is quit() or until a single poll() blocks for more than "timeout"
milliseconds. But that's pretty different than what we want here which is the
following: run as many tasks from the queue as you want and block as many times
as you want, but don't spend more than getReadTimeout() milliseconds in total.

This version would be correct if you knew that a single task would be enough and
that no other tasks can be in the queue. Even if that happens to be true today,
it seems pretty brittle.

Instead, consider having MessageLoop.loop() interpret "timeout" as the time
budget for the whole call. Each time around the loop, compute how much time
remains before that deadline and pass that number as the timeout to poll().

[xunjieli, 2016/05/17 19:43:07]

Talked to Andrei. MessageLoop is our internal implementation detail. There is
only one MessageLoop per HttpURLConnection. When user calls InputStream.read(),
we will time out exactly after getReadTimeout(), so we think this what you want.

     }
 
     /**
@@ -516,7 +516,7 @@ public class CronetHttpURLConnection extends HttpURLConnection {
         if (!mHasResponse) {
             startRequest();
             // Blocks until onResponseStarted or onFailed is called.
-            mMessageLoop.loop();
+            mMessageLoop.loop(getConnectTimeout());
             mHasResponse = true;
         }
         checkHasResponse();