Change getDevices to use a DeviceCallback.

chrome/renderer/resources/extensions/experimental.bluetooth_custom_bindings.js

Index: chrome/renderer/resources/extensions/experimental.bluetooth_custom_bindings.js
diff --git a/chrome/renderer/resources/extensions/experimental.bluetooth_custom_bindings.js b/chrome/renderer/resources/extensions/experimental.bluetooth_custom_bindings.js
index 76f525b84bcfd31173dbe67144098689e0f7b685..4c18c4f1a955fdc35238bd83779acd5df331e2b3 100644
--- a/chrome/renderer/resources/extensions/experimental.bluetooth_custom_bindings.js
+++ b/chrome/renderer/resources/extensions/experimental.bluetooth_custom_bindings.js
@@ -15,16 +15,15 @@ chromeHidden.registerCustomHook('experimental.bluetooth', function(api) {
   var apiFunctions = api.apiFunctions;
 
   chromeHidden.bluetooth = {};
+
   chromeHidden.bluetooth.deviceDiscoveredHandler = null;
   chromeHidden.bluetooth.onDeviceDiscovered =
       new chrome.Event("experimental.bluetooth.onDeviceDiscovered");
-
   function clearDeviceDiscoveredHandler() {
     chromeHidden.bluetooth.onDeviceDiscovered.removeListener(
         chromeHidden.bluetooth.deviceDiscoveredHandler);
     chromeHidden.bluetooth.deviceDiscoveredHandler = null;
   }
-
   apiFunctions.setHandleRequest('startDiscovery',
       function() {
         var args = arguments;
@@ -58,4 +57,35 @@ chromeHidden.registerCustomHook('experimental.bluetooth', function(api) {
         clearDeviceDiscoveredHandler();
         sendRequest(this.name, arguments, this.definition.parameters);
       });
+
+  chromeHidden.bluetooth.deviceSearchResultHandler = null;
+  chromeHidden.bluetooth.onDeviceSearchResult =
+      new chrome.Event("experimental.bluetooth.onDeviceSearchResult");
+  apiFunctions.setHandleRequest('getDevices',
+      function() {
+        var args = arguments;
+        if (args.length > 0 && args[0] && args[0].deviceCallback) {
+          chromeHidden.bluetooth.deviceSearchResultHandler =
+              args[0].deviceCallback;
+          chromeHidden.bluetooth.onDeviceSearchResult.addListener(
+              chromeHidden.bluetooth.deviceSearchResultHandler);

[asargent_no_longer_on_chrome, 2012/09/11 17:42:56]

It looks like your intention is to only handle a single outstanding request to
getDevices at a time from a given script context, but you don't seem to enforce
that here, so you can clobber the reference to the outstanding call's listener,
and then in setCustomCallback you'll remove the wrong one. 

I think you want to check if deviceSearchResultHandler is null and return an
error if it isn't. 

Alternatively, if you wanted to allow multiple outstanding calls to getDevices
(does the C++ code support that?) you could keep a map of references to
listeners keyed by request id. I believe the request id is hung off the request
object that your setHandleRequest and setCustomCallback gets called with. 

[bryeung, 2012/09/11 18:37:30]

Great catch.

I'm fine with disallowing concurrent calls to these methods.  I've updated the
code and added a test for the getDevices case.

+          sendRequest(this.name,
+                      args,
+                      this.definition.parameters,
+                      {customCallback:this.customCallback});
+        } else {
+          if (typeof(args[args.length-1]) == "function") {
+            var callback = args[args.length-1];
+            lastError.set("deviceCallback is required in the options object");
+            callback();
+            return;
+          }
+        }
+      });
+  apiFunctions.setCustomCallback('getDevices',
+      function(name, request, response) {
+        chromeHidden.bluetooth.onDeviceSearchResult.removeListener(
+            chromeHidden.bluetooth.deviceSearchResultHandler);
+        chromeHidden.bluetooth.deviceSearchResultHandler = null;
+      });
 });