First pass at experimental omnibox API. There are plenty of rough edges and

chrome/browser/extensions/extension_omnibox_apitest.cc

+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/autocomplete/autocomplete.h"
+#include "chrome/browser/autocomplete/autocomplete_edit.h"
+#include "chrome/browser/autocomplete/autocomplete_edit_view.h"
+#include "chrome/browser/autocomplete/autocomplete_popup_model.h"
+#include "chrome/browser/browser.h"
+#include "chrome/browser/browser_window.h"
+#include "chrome/browser/extensions/extension_apitest.h"
+#include "chrome/browser/history/history.h"
+#include "chrome/browser/location_bar.h"
+#include "chrome/browser/profile.h"
+#include "chrome/common/chrome_switches.h"
+#include "chrome/common/notification_type.h"
+#include "chrome/common/url_constants.h"
+#include "chrome/test/ui_test_utils.h"
+
+namespace {
+
+std::wstring AutocompleteResultAsString(const AutocompleteResult& result) {
+  std::wstring output(StringPrintf(L"{%d} ", result.size()));
+  for (size_t i = 0; i < result.size(); ++i) {
+    AutocompleteMatch match = result.match_at(i);
+    std::wstring provider_name(ASCIIToWide(match.provider->name()));
+    output.append(StringPrintf(L"[\"%ls\" by \"%ls\"] ",
+                               match.contents.c_str(),
+                               provider_name.c_str()));
+  }
+  return output;
+}
+
+}  // namespace
+
+class OmniboxApiTest : public ExtensionApiTest {
+ protected:
+  LocationBar* GetLocationBar() const {
+    return browser()->window()->GetLocationBar();
+  }
+
+  AutocompleteController* GetAutocompleteController() const {
+    return GetLocationBar()->location_entry()->model()->popup_model()->
+        autocomplete_controller();
+  }
+
+  void WaitForHistoryBackendToLoad() {
+    HistoryService* history_service =
+        browser()->profile()->GetHistoryService(Profile::EXPLICIT_ACCESS);
+    if (!history_service->BackendLoaded())
+      ui_test_utils::WaitForNotification(NotificationType::HISTORY_LOADED);
+  }
+
+  void WaitForAutocompleteDone(AutocompleteController* controller) {
+    while (!controller->done()) {
+      ui_test_utils::WaitForNotification(
+          NotificationType::AUTOCOMPLETE_CONTROLLER_DEFAULT_MATCH_UPDATED);
+    }
+  }
+};
+
+IN_PROC_BROWSER_TEST_F(OmniboxApiTest, Basic) {
+  CommandLine::ForCurrentProcess()->AppendSwitch(
+      switches::kEnableExperimentalExtensionApis);
+
+  ASSERT_TRUE(StartHTTPServer());
+  ASSERT_TRUE(RunExtensionTest("omnibox")) << message_;
+
+  // The results depend on the history backend being loaded. Make sure it is
+  // loaded so that the autocomplete results are consistent.
+  WaitForHistoryBackendToLoad();
+
+  LocationBar* location_bar = GetLocationBar();
+  AutocompleteController* autocomplete_controller = GetAutocompleteController();
+
+  // Test that our extension's keyword is suggested to us when we partially type
+  // it.
+  {
+    autocomplete_controller->Start(L"keywor", std::wstring(),
+                                   true, false, false);
+
+    WaitForAutocompleteDone(autocomplete_controller);
+    EXPECT_TRUE(autocomplete_controller->done());
+    EXPECT_EQ(std::wstring(), location_bar->GetInputString());
+    EXPECT_EQ(std::wstring(), location_bar->location_entry()->GetText());
+    EXPECT_TRUE(location_bar->location_entry()->IsSelectAll());
+
+    // First result should be to search for what was typed, second should be to
+    // enter "extension keyword" mode.
+    const AutocompleteResult& result = autocomplete_controller->result();
+    ASSERT_EQ(2U, result.size()) << AutocompleteResultAsString(result);
+    AutocompleteMatch match = result.match_at(0);
+    EXPECT_EQ(AutocompleteMatch::SEARCH_WHAT_YOU_TYPED, match.type);
+    EXPECT_FALSE(match.deletable);
+
+    match = result.match_at(1);
+    ASSERT_TRUE(match.template_url);
+    EXPECT_TRUE(match.template_url->IsExtensionKeyword());
+    EXPECT_EQ(L"keyword", match.template_url->keyword());
+  }
+
+  // Test that our extension can send suggestions back to us.
+  {
+    autocomplete_controller->Start(L"keyword suggestio", std::wstring(),
+                                   true, false, false);
+
+    WaitForAutocompleteDone(autocomplete_controller);
+    EXPECT_TRUE(autocomplete_controller->done());
+
+    // First result should be to invoke the keyword with what we typed, 2-4
+    // should be to invoke with suggestions from the extension, and the last
+    // should be to search for what we typed.
+    const AutocompleteResult& result = autocomplete_controller->result();
+    ASSERT_EQ(5U, result.size()) << AutocompleteResultAsString(result);
+
+    ASSERT_TRUE(result.match_at(0).template_url);
+    EXPECT_EQ(L"keyword suggestio", result.match_at(0).fill_into_edit);
+    EXPECT_EQ(L"keyword suggestion1", result.match_at(1).fill_into_edit);
+    EXPECT_EQ(L"keyword suggestion2", result.match_at(2).fill_into_edit);
+    EXPECT_EQ(L"keyword suggestion3", result.match_at(3).fill_into_edit);
+
+    AutocompleteMatch match = result.match_at(4);
+    EXPECT_EQ(AutocompleteMatch::SEARCH_WHAT_YOU_TYPED, match.type);
+    EXPECT_FALSE(match.deletable);
+  }
+
+  {
+    ResultCatcher catcher;
+    autocomplete_controller->Start(L"keyword command", std::wstring(),
+                                   true, false, false);
+    location_bar->AcceptInput();
+    EXPECT_TRUE(catcher.GetNextResult()) << catcher.message();
+  }
+}