Update references to the extension messaging APIs to point to the "runtime"

chrome/renderer/resources/extensions/miscellaneous_bindings.js

Index: chrome/renderer/resources/extensions/miscellaneous_bindings.js
diff --git a/chrome/renderer/resources/extensions/miscellaneous_bindings.js b/chrome/renderer/resources/extensions/miscellaneous_bindings.js
index 9904e8cf850b746bc56cc164b4df77918d98fca9..5663271ca30514206ac95f399c689852f03572aa 100644
--- a/chrome/renderer/resources/extensions/miscellaneous_bindings.js
+++ b/chrome/renderer/resources/extensions/miscellaneous_bindings.js
@@ -255,7 +255,7 @@
     }
   };
 
-  // Shared implementation used by tabs.sendMessage and extension.sendMessage.
+  // Shared implementation used by tabs.sendMessage and runtime.sendMessage.
   chromeHidden.Port.sendMessageImpl = function(port, request,
                                                responseCallback) {
     if (port.name != chromeHidden.kNativeMessageChannel)