Pass pepper apps API calls through the existing js apps API bindings.

chrome/renderer/resources/extensions/pepper_request.js

Index: chrome/renderer/resources/extensions/pepper_request.js
diff --git a/chrome/renderer/resources/extensions/pepper_request.js b/chrome/renderer/resources/extensions/pepper_request.js
new file mode 100644
index 0000000000000000000000000000000000000000..b90b35d279d0d2bba93abee889d68818590c8de6
--- /dev/null
+++ b/chrome/renderer/resources/extensions/pepper_request.js
@@ -0,0 +1,51 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var SendResponse = requireNative('pepper_request_natives').SendResponse;
+var GetAvailability = requireNative('v8_context').GetAvailability;
+
+function checkAvailability(name) {
+  var availability = GetAvailability(name);
+  if (!availability.is_available)
+    throw Error(availability.message);
+}
+
+function resolveName(name) {
+  checkAvailability(name);

[not at google - send to devlin, 2013/12/03 17:32:50]

having checkAvailability be a separate method doesn't add much.

[Sam McNally, 2013/12/04 00:01:36]

Done.

+  var item = chrome;
+  var nameComponents = $String.split(name, '.');
+  for (var i = 0; i < nameComponents.length; i++) {
+    item = item[nameComponents[i]];
+  }
+  return item;
+}
+
+function callMethod(targetName, requestId) {
+  var args = $Array.slice(arguments, 2);
+  args.push(function() {
+    var error = null;
+    if (chrome.runtime.lastError)
+      error = chrome.runtime.lastError.message;
+    SendResponse(requestId, $Array.slice(arguments), error);
+  });
+  try {
+    var target = resolveName(targetName);
+    $Function.apply(target, null, args);
+  } catch (e) {
+    return e.message;

[not at google - send to devlin, 2013/12/03 17:32:50]

It would probably be nicer to catch this error from C++ but I can see that the
ModuleSystem doesn't like that.

We can fix this later - probably by having some interface like

ModuleSystem::ScopedExceptionCatcher exception_catcher(module_system);
module_system->CallModuleMethod(...);
if (exception_catcher.HasCaught...)
  ...

but for now could you add a TODO?

[Sam McNally, 2013/12/04 00:01:36]

Done.

+  }
+}
+
+function postMethod(targetName) {

[not at google - send to devlin, 2013/12/03 17:32:50]

if you kill StartPost then you'd kill this method too, but I think that's fine.
the extra work in doing that SendResponse etc is negligible.

[Sam McNally, 2013/12/04 00:01:36]

Done.

+  var args = $Array.slice(arguments, 1);
+  try {
+    var target = resolveName(targetName);
+    $Function.apply(target, null, args);
+  } catch (e) {
+    return e.message;
+  }
+}
+
+exports.callMethod = callMethod;
+exports.postMethod = postMethod;