Add a PermissionDeniedError, update Push API public API

Source/bindings/core/v8/PrivateScriptRunner.js

Index: Source/bindings/core/v8/PrivateScriptRunner.js
diff --git a/Source/bindings/core/v8/PrivateScriptRunner.js b/Source/bindings/core/v8/PrivateScriptRunner.js
index cd8f78d4f29f16f7fea7d200324595dd19f3c295..9dc27f0d7df329ed178c35aa4b557e776261c367 100644
--- a/Source/bindings/core/v8/PrivateScriptRunner.js
+++ b/Source/bindings/core/v8/PrivateScriptRunner.js
@@ -60,6 +60,9 @@ function PrivateScriptController()
 
         // Web Crypto
         "OperationError",
+
+        // Push API

[johnme, 2015/08/27 16:09:08]

Nit: Shouldn't this be a more generic section? "Permissions"?

Ditto below several times.

Maybe also link to https://www.w3.org/Bugs/Public/show_bug.cgi?id=23033 as well
here.

[Peter Beverloo, 2015/08/27 16:24:31]

So far this is Push API specific (though media streams is likely to adopt this
as well). I don't think a comment named permissions is much more useful,
however. I'll see what the owners think.

+        "PermissionDeniedError",
     ];
 
     // This list must be in sync with the enum in ExceptionCode.h. The order matters.