Fix issues related to request and context object lifespan (issue #1037, issue #1044).

- Simplify and document the relationship between the various context object types. See browser_context.h for a description of the new relationships.
- cefclient: Add `request-context-per-browser` command-line flag for testing multiple CefRequestContext instances.
- cefclient: Add a CefURLRequest example.

git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@2032 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

tests/cefclient/browser/resource_util_win.cc

@@ -45,6 +45,7 @@ int GetResourceId(const char* resource_name) {
     {"performance.html", IDS_PERFORMANCE},
     {"performance2.html", IDS_PERFORMANCE2},
     {"transparency.html", IDS_TRANSPARENCY},
+    {"urlrequest.html", IDS_URLREQUEST},
     {"window.html", IDS_WINDOW},
     {"xmlhttprequest.html", IDS_XMLHTTPREQUEST},
   };