Exposing extension preferences via the `chrome.extension` API.

`chrome.extension.isAllowedIncognitoAccess` gives access to `chrome://extension`'s "Allowed in Incognito" checkbox's state, and `chrome.extension.isAllowedFileSchemeAccess` does the same for "Allow access to File URLs".

Patch by Mike West <[email protected]>.

BUG=74694
TEST=Create an extension that checks whether 'Allow in Incognito' or 'Allow access to File URLs' is checked.  It should work correctly.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@78347 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/extensions/extension_function_dispatcher.cc b/chrome/browser/extensions/extension_function_dispatcher.cc
index 1d58b498..f3c805d 100644
--- a/chrome/browser/extensions/extension_function_dispatcher.cc
+++ b/chrome/browser/extensions/extension_function_dispatcher.cc
@@ -283,6 +283,8 @@
 
   // Extension module.
   RegisterFunction<SetUpdateUrlDataFunction>();
+  RegisterFunction<IsAllowedIncognitoAccessFunction>();
+  RegisterFunction<IsAllowedFileSchemeAccessFunction>();
 
   // WebstorePrivate.
   RegisterFunction<GetBrowserLoginFunction>();