[Remoting Android] Refactor OAuth Token Fetching Code

remoting/android/java/src/org/chromium/chromoting/HostListManager.java

Index: remoting/android/java/src/org/chromium/chromoting/HostListManager.java
diff --git a/remoting/android/java/src/org/chromium/chromoting/HostListManager.java b/remoting/android/java/src/org/chromium/chromoting/HostListManager.java
index 64fb6658cbc830d48a6b8fa1e18725b7b9721eed..200fb7a0a68305df1f93a3ae3457850d1b1bca21 100644
--- a/remoting/android/java/src/org/chromium/chromoting/HostListManager.java
+++ b/remoting/android/java/src/org/chromium/chromoting/HostListManager.java
@@ -275,6 +275,7 @@ public class HostListManager {
             int status = link.getResponseCode();
             switch (status) {
                 case HttpURLConnection.HTTP_OK:  // 200
+                case HttpURLConnection.HTTP_NO_CONTENT:  // 204

[Yuwei, 2016/05/13 00:30:17]

This is a quick fix for the HostListManager. Turns out the server will respond
to the delete operation with 204 status code.

[Lambros, 2016/05/13 01:11:31]

We should probably replace this switch-statement with testing ranges of HTTP
codes.
200-299 are all OK, 400-499 are AUTH_FAILED, 500-599 are SERVICE_UNAVAILABLE,
everything else is UNKNOWN.

We've had problems in the past where the server returned a different code than
expected, so now might be a good time to make this change?

Doesn't need to hold up this CL if you want to do it separately.

[Yuwei, 2016/05/13 03:53:58]

Sure. I'll add a TODO here. BTW I think only 401 is for AUTH_FAILED. 4XX can be
not found and incorrect request, etc...

                     break;
                 case HttpURLConnection.HTTP_UNAUTHORIZED:  // 401
                     error = Error.AUTH_FAILED;