First pass as implementing the greasemonkey API. This patch

chrome/renderer/user_script_slave.h

Index: chrome/renderer/user_script_slave.h
diff --git a/chrome/renderer/user_script_slave.h b/chrome/renderer/user_script_slave.h
index dd409603290ce44670fc981c6537755e96748ff2..21b67dc355e0f0141397782de521cf4acd876117 100644
--- a/chrome/renderer/user_script_slave.h
+++ b/chrome/renderer/user_script_slave.h
@@ -89,6 +89,14 @@ class UserScriptSlave {
   // Parsed script data.
   std::vector<UserScript> scripts_;
 
+  // Greasemonkey API source that is injected with the scripts.
+  StringPiece api_js_;
+
+  // The line number of the first line of the user script among all of the
+  // injected javascript.  This is used to make reported errors correspond with
+  // the proper line in the user script.
+  int user_script_start_line_;
+
   DISALLOW_COPY_AND_ASSIGN(UserScriptSlave);
 };