Functionality has been requested in the Extension API for Javascript to...

chrome/renderer/extensions/extension_api_client_unittest.cc

Index: chrome/renderer/extensions/extension_api_client_unittest.cc
diff --git a/chrome/renderer/extensions/extension_api_client_unittest.cc b/chrome/renderer/extensions/extension_api_client_unittest.cc
index 5465a5ce710d4385fce9284b318a8cbcc09c322a..49136c5131ae6757dfea84a5cdab17f6ff972d54 100644
--- a/chrome/renderer/extensions/extension_api_client_unittest.cc
+++ b/chrome/renderer/extensions/extension_api_client_unittest.cc
@@ -422,6 +422,18 @@ TEST_F(ExtensionAPIClientTest, RemoveTab) {
                "tabs.remove", "2");
 }
 
+TEST_F(ExtensionAPIClientTest, CaptureVisibleTab) {
+  ExpectJsFail("chrome.tabs.captureVisibleTab(0);",
+               "Uncaught Error: Parameter 1 is required.");
+
+  ExpectJsFail("chrome.tabs.captureVisibleTab(function(){}, 0)",
+               "Uncaught Error: Invalid value for argument 0. "
+               "Expected 'integer' but got 'function'.");
+
+  ExpectJsPass("chrome.tabs.captureVisibleTab(null, function(img){});",
+               "tabs.captureVisibleTab", "null");
+}
+
 // Bookmark API tests
 // TODO(erikkay) add more variations here