Implement signin using webview

extensions/browser/extension_function_dispatcher.cc

Index: extensions/browser/extension_function_dispatcher.cc
diff --git a/extensions/browser/extension_function_dispatcher.cc b/extensions/browser/extension_function_dispatcher.cc
index f9bbec561b911df0eadb21606c01769ed0b4916f..659096eecc8fa4d11c98165699e04f2d28f15264 100644
--- a/extensions/browser/extension_function_dispatcher.cc
+++ b/extensions/browser/extension_function_dispatcher.cc
@@ -11,6 +11,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/metrics/sparse_histogram.h"
 #include "base/process/process.h"
+#include "base/strings/string_util.h"
 #include "base/values.h"
 #include "build/build_config.h"
 #include "content/public/browser/browser_thread.h"
@@ -229,8 +230,8 @@ void ExtensionFunctionDispatcher::DispatchOnIOThread(
     const ExtensionHostMsg_Request_Params& params) {
   const Extension* extension =
       extension_info_map->extensions().GetByID(params.extension_id);
-  if (!extension)
-    return;
+  const std::string& extension_id = extension ?
+      extension->id() : base::EmptyString();
 
   ExtensionFunction::ResponseCallback callback(
       base::Bind(&IOThreadResponseCallback, ipc_sender, routing_id,
@@ -256,19 +257,17 @@ void ExtensionFunctionDispatcher::DispatchOnIOThread(
   function_io->set_ipc_sender(ipc_sender, routing_id);
   function_io->set_extension_info_map(extension_info_map);
   function->set_include_incognito(
-      extension_info_map->IsIncognitoEnabled(extension->id()));
+      extension_info_map->IsIncognitoEnabled(extension_id));
 
   if (!CheckPermissions(function.get(), params, callback))
     return;
 
   QuotaService* quota = extension_info_map->GetQuotaService();
-  std::string violation_error = quota->Assess(extension->id(),
-                                              function.get(),
-                                              &params.arguments,
-                                              base::TimeTicks::Now());
+  std::string violation_error = quota->Assess(
+      extension_id, function.get(), &params.arguments, base::TimeTicks::Now());
   if (violation_error.empty()) {
     scoped_ptr<base::ListValue> args(params.arguments.DeepCopy());
-    NotifyApiFunctionCalled(extension->id(),
+    NotifyApiFunctionCalled(extension_id,
                             params.name,
                             args.Pass(),
                             static_cast<content::BrowserContext*>(profile_id));