Allow content script insertion on about:-URLs.

extensions/common/url_pattern.h

Index: extensions/common/url_pattern.h
diff --git a/extensions/common/url_pattern.h b/extensions/common/url_pattern.h
index a04a2f2545fa766281404687359d3310a722ea83..070abe21e6cc21a6a658989d5a833ade5da4f57b 100644
--- a/extensions/common/url_pattern.h
+++ b/extensions/common/url_pattern.h
@@ -15,7 +15,7 @@ class GURL;
 //
 // <url-pattern> := <scheme>://<host><port><path> | '<all_urls>'
 // <scheme> := '*' | 'http' | 'https' | 'file' | 'ftp' | 'chrome' |
-//             'chrome-extension' | 'filesystem'
+//             'chrome-extension' | 'filesystem' | 'about'
 // <host> := '*' | '*.' <anychar except '/' and '*'>+
 // <port> := [':' ('*' | <port number between 0 and 65535>)]
 // <path> := '/' <any chars>
@@ -52,6 +52,7 @@ class URLPattern {
     SCHEME_CHROMEUI   = 1 << 4,
     SCHEME_EXTENSION  = 1 << 5,
     SCHEME_FILESYSTEM = 1 << 6,
+    SCHEME_ABOUT      = 1 << 7,
 
     // IMPORTANT!
     // SCHEME_ALL will match every scheme, including chrome://, chrome-