Handle extension webrequest API on the IO thread. This speeds up blocking event

chrome/renderer/resources/extension_process_bindings.js

Index: chrome/renderer/resources/extension_process_bindings.js
diff --git a/chrome/renderer/resources/extension_process_bindings.js b/chrome/renderer/resources/extension_process_bindings.js
index af682c07e189a3c97fa5363260f7862ab0a1cc22..8e33dab6a820775c8c8a3923f044f2b99efa02b3 100644
--- a/chrome/renderer/resources/extension_process_bindings.js
+++ b/chrome/renderer/resources/extension_process_bindings.js
@@ -9,6 +9,7 @@ var chrome = chrome || {};
 (function() {
   native function GetExtensionAPIDefinition();
   native function StartRequest();
+  native function StartRequestForIOThread();
   native function GetCurrentPageActions(extensionId);
   native function GetExtensionViews();
   native function GetChromeHidden();
@@ -183,31 +184,26 @@ var chrome = chrome || {};
   }
 
   // Send an API request and optionally register a callback.
-  function sendRequest(functionName, args, argSchemas, customCallback) {
+  // If |opt_rawargs| is true, don't JSONify the arguments. If
+  // |opt_nativeFunction| is provided, use that instead of StartRequest.
+  function sendRequest(functionName, args, argSchemas, opt_customCallback,

[Mihai Parparita -not on Chrome, 2011/06/08 01:11:59]

The callsites of this are confusing to follow because of all the optional
arguments. Perhaps have a sendRequestOnIOThread wrapper (and sendIconRequest for
the other usecase)?

[Matt Perry, 2011/06/08 20:47:00]

I've changed the optional arguments to a single optional object with named args.
Does that clarify it enough?

+                       opt_rawargs, opt_nativeFunction) {
     var request = prepareRequest(args, argSchemas);
-    if (customCallback) {
-      request.customCallback = customCallback;
+    if (opt_customCallback) {
+      request.customCallback = opt_customCallback;
     }
     // JSON.stringify doesn't support a root object which is undefined.
     if (request.args === undefined)
       request.args = null;
 
-    var sargs = chromeHidden.JSON.stringify(request.args);
+    var sargs = opt_rawargs ?
+        request.args : chromeHidden.JSON.stringify(request.args);
+    var nativeFunction = opt_nativeFunction || StartRequest;
 
     var requestId = GetNextRequestId();
     requests[requestId] = request;
-    var hasCallback = (request.callback || customCallback) ? true : false;
-    return StartRequest(functionName, sargs, requestId, hasCallback);
-  }
-
-  // Send a special API request that is not JSON stringifiable, and optionally
-  // register a callback.
-  function sendCustomRequest(nativeFunction, functionName, args, argSchemas) {
-    var request = prepareRequest(args, argSchemas);
-    var requestId = GetNextRequestId();
-    requests[requestId] = request;
-    return nativeFunction(functionName, request.args, requestId,
-                          request.callback ? true : false);
+    var hasCallback = (request.callback || opt_customCallback) ? true : false;
+    return nativeFunction(functionName, sargs, requestId, hasCallback);
   }
 
   // Helper function for positioning pop-up windows relative to DOM objects.
@@ -750,7 +746,7 @@ var chrome = chrome || {};
               "is no larger than " + iconSize + " pixels square.");
         }
 
-        sendCustomRequest(nativeFunction, name, [details], parameters);
+        sendRequest(name, [details], parameters, null, true, nativeFunction);
       } else if ("path" in details) {
         var img = new Image();
         img.onerror = function() {
@@ -768,7 +764,7 @@ var chrome = chrome || {};
           delete details.path;
           details.imageData = canvas_context.getImageData(0, 0, canvas.width,
                                                           canvas.height);
-          sendCustomRequest(nativeFunction, name, [details], parameters);
+          sendRequest(name, [details], parameters, null, true, nativeFunction);
         };
         img.src = details.path;
       } else {
@@ -818,6 +814,20 @@ var chrome = chrome || {};
       sendRequest(this.name, [parseResult], this.definition.parameters);
     };
 
+    apiFunctions["experimental.webRequest.addEventListener"].handleRequest =
+        function() {
+      var args = Array.prototype.slice.call(arguments);
+      sendRequest(this.name, args, this.definition.parameters,
+                  null, false, StartRequestForIOThread);
+    };
+
+    apiFunctions["experimental.webRequest.eventHandled"].handleRequest =
+        function() {
+      var args = Array.prototype.slice.call(arguments);
+      sendRequest(this.name, args, this.definition.parameters,
+                  null, false, StartRequestForIOThread);
+    };
+
     apiFunctions["contextMenus.create"].customCallback =
         function(name, request, response) {
       if (chrome.extension.lastError) {