Allow NaCl plugin to be loaded from hosted app URLs.

chrome/test/data/extensions/native_client_hosted_app/manifest.json

Index: chrome/test/data/extensions/native_client_hosted_app/manifest.json
===================================================================
--- chrome/test/data/extensions/native_client_hosted_app/manifest.json	(revision 0)
+++ chrome/test/data/extensions/native_client_hosted_app/manifest.json	(revision 0)
@@ -0,0 +1,14 @@
+{
+  "name": "chrome.native_client.hosted_app",
+  "version": "0.1",
+  "manifest_version": 2,
+  "description": "end-to-end browser test for native client in hosted apps",
+  "app": {
+    "urls": [
+      "http://localhost/files/extensions/native_client"
+    ],
+    "launch": {
+      "web_url": "http://localhost/files/extensions/native_client/test.html"
+    }
+  }
+}