[Cronet] Replace setExperimentalQuicConnectionOptions with a more general API

components/cronet/android/api/src/org/chromium/net/CronetEngine.java

Index: components/cronet/android/api/src/org/chromium/net/CronetEngine.java
diff --git a/components/cronet/android/api/src/org/chromium/net/CronetEngine.java b/components/cronet/android/api/src/org/chromium/net/CronetEngine.java
index 29fd3f01b0f285697e89737f794787092f4dc0a5..a6af620ed7489fb3774d3d56d4255b8fcccdf4c8 100644
--- a/components/cronet/android/api/src/org/chromium/net/CronetEngine.java
+++ b/components/cronet/android/api/src/org/chromium/net/CronetEngine.java
@@ -301,15 +301,12 @@ public abstract class CronetEngine {
         }
 
         /**
-         * Sets experimental QUIC connection options, overwriting any pre-existing
-         * options. List of options is subject to change.
+         * Sets experimental options to be used in Cronet.
          *
-         * @param quicConnectionOptions comma-separated QUIC options (for example
-         * "PACE,IW10") to use if QUIC is enabled.
-         * @return the builder to facilitate chaining.
+         * @param options JSON formatted experimental options

[mef, 2015/11/06 18:52:39]

nits: in this file we end param@ comments with period. 
Also may want to restore the @return comment.

[xunjieli, 2015/11/13 22:13:06]

Done.

          */
-        public Builder setExperimentalQuicConnectionOptions(String quicConnectionOptions) {
-            return putString(CronetEngineBuilderList.QUIC_OPTIONS, quicConnectionOptions);
+        public Builder setExperimentalOptions(String options) {
+            return putString(CronetEngineBuilderList.EXPERIMENTAL_OPTIONS, options);

[mef, 2015/11/06 18:52:39]

Given that engine building is slow and rare I think it might be worth it to add
a check that options is valid JSON string by trying to load it into JSONObject.

[xunjieli, 2015/11/13 22:13:06]

Do we add a "throws JSONException" to the method signature? or should we catch
the checked exception and throw a runtime exception?
I am not sure if that necessary. We do have a dcheck in
url_request_context_config.cc to make sure it is a json.

         }
 
         /**