Check for warnings when loading extensions in browser tests.

chrome/test/data/extensions/api_test/stubs/content_script.js

Index: chrome/test/data/extensions/api_test/stubs/content_script.js
diff --git a/chrome/test/data/extensions/api_test/stubs/content_script.js b/chrome/test/data/extensions/api_test/stubs/content_script.js
index dfdb0e7a5102518a2a186c302f419799deda7425..1b3f2ebc9e695ccdb2179b1c11d37915c43a22cc 100644
--- a/chrome/test/data/extensions/api_test/stubs/content_script.js
+++ b/chrome/test/data/extensions/api_test/stubs/content_script.js
@@ -24,6 +24,12 @@ chrome.extension.sendRequest("getApi", function(apis) {
       if (typeof(module[section]) == "undefined")
         return;
       module[section].forEach(function(entry) {
+        // Ignore entries that are not applicable to the manifest that we're
+        // running under.
+        if (entry.maximumManifestVersion && entry.maximumManifestVersion < 2) {
+          return;
+        }
+
         var path = namespace + "." + entry.name;
         if (module.unprivileged || entry.unprivileged) {
           unprivilegedPaths.push(path);