Add PyAuto tests for triggering browser/page action.

chrome/browser/automation/testing_automation_provider.h

Index: chrome/browser/automation/testing_automation_provider.h
diff --git a/chrome/browser/automation/testing_automation_provider.h b/chrome/browser/automation/testing_automation_provider.h
index 3402685b1c331b5407352fc9159a2ba1d0f50b25..f40d93135d1a543a599397736a129496db5cd808 100644
--- a/chrome/browser/automation/testing_automation_provider.h
+++ b/chrome/browser/automation/testing_automation_provider.h
@@ -652,6 +652,12 @@ class TestingAutomationProvider : public AutomationProvider,
                              base::DictionaryValue* args,
                              IPC::Message* reply_message);
 
+  // Trigger browser/page action asynchronously in the active tab.
+  // Uses the JSON interface for input/output.
+  void TriggerExtensionActionById(Browser* browser,
+                                  base::DictionaryValue* args,
+                                  IPC::Message* reply_message);
+
   // Responds to the Find request and returns the match count.
   void FindInPage(Browser* browser,
                   base::DictionaryValue* args,