Allow chromedriver to install an extension and get all installed extension IDs.

chrome/test/automation/automation_json_requests.h

Index: chrome/test/automation/automation_json_requests.h
diff --git a/chrome/test/automation/automation_json_requests.h b/chrome/test/automation/automation_json_requests.h
index ada6d8d538f3a0d81df705e67055bf87183e6d71..28d607d334d6a466747a8cb020b6b1f32b4359e9 100644
--- a/chrome/test/automation/automation_json_requests.h
+++ b/chrome/test/automation/automation_json_requests.h
@@ -317,4 +317,19 @@ bool SendGetChromeDriverAutomationVersion(
     int* version,
     std::string* error_msg) WARN_UNUSED_RESULT;
 
+// Requests info about all installed extensions. Returns true on success.
+bool SendGetExtensionsInfoJSONRequest(
+    AutomationMessageSender* sender,
+    base::ListValue* extensions_list,
+    std::string* error_msg) WARN_UNUSED_RESULT;
+
+// Requests that the given extension be installed. If |with_ui| is false,
+// the extension will be installed silently. Returns true on success.
+bool SendInstallExtensionJSONRequest(
+    AutomationMessageSender* sender,
+    const FilePath& path,
+    bool with_ui,
+    std::string* extension_id,
+    std::string* error_msg) WARN_UNUSED_RESULT;
+
 #endif  // CHROME_TEST_AUTOMATION_AUTOMATION_JSON_REQUESTS_H_