Simplify ZoomController by removing DefaultZoomLevel prefs machinery.

chrome/browser/ui/zoom/zoom_controller_browsertest.cc

 // Copyright 2014 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/ui/zoom/zoom_controller.h"
 
+#include "base/prefs/pref_service.h"
 #include "base/process/kill.h"
+#include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
+#include "chrome/common/pref_names.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/test/browser_test_utils.h"
+#include "testing/gmock/include/gmock/gmock.h"
 
 typedef InProcessBrowserTest ZoomControllerBrowserTest;
 
+bool operator==(const ZoomController::ZoomChangedEventData& lhs,
+                const ZoomController::ZoomChangedEventData& rhs) {
+  return lhs.web_contents == rhs.web_contents &&
+         lhs.old_zoom_level == rhs.old_zoom_level &&
+         lhs.new_zoom_level == rhs.new_zoom_level &&
+         lhs.zoom_mode == rhs.zoom_mode &&
+         lhs.can_show_bubble == rhs.can_show_bubble;
+}
+
+class ZoomChangedWatcher : public ZoomObserver {
+ public:
+  ZoomChangedWatcher(
+      content::WebContents* web_contents,
+      const ZoomController::ZoomChangedEventData& expected_event_data)
+      : web_contents_(web_contents),
+        expected_event_data_(expected_event_data),
+        message_loop_runner_(new content::MessageLoopRunner) {
+    ZoomController::FromWebContents(web_contents)->AddObserver(this);
+  }
+  virtual ~ZoomChangedWatcher() {}
+
+  void Wait() { message_loop_runner_->Run(); }
+
+  virtual void OnZoomChanged(
+      const ZoomController::ZoomChangedEventData& event_data) OVERRIDE {
+    if (event_data == expected_event_data_)
+      message_loop_runner_->Quit();
+  }
+
+ private:
+  content::WebContents* web_contents_;
+  ZoomController::ZoomChangedEventData expected_event_data_;
+  scoped_refptr<content::MessageLoopRunner> message_loop_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(ZoomChangedWatcher);
+};
+
 // TODO(wjmaclean): Enable this on Android when we can kill the process there.
 #if defined(OS_ANDROID)
 #define MAYBE_CrashedTabsDoNotChangeZoom DISABLED_CrashedTabsDoNotChangeZoom
 #else
 #define MAYBE_CrashedTabsDoNotChangeZoom CrashedTabsDoNotChangeZoom
 #endif
 IN_PROC_BROWSER_TEST_F(ZoomControllerBrowserTest,
                        MAYBE_CrashedTabsDoNotChangeZoom) {
   // At the start of the test we are at a tab displaying about:blank.
   content::WebContents* web_contents =
@@ skipping 12 matching lines @@
     base::KillProcess(host->GetHandle(), 0, false);
     crash_observer.Wait();
   }
   EXPECT_FALSE(web_contents->GetRenderProcessHost()->HasConnection());
 
   // The following attempt to change the zoom level for a crashed tab should
   // fail.
   zoom_controller->SetZoomLevel(new_zoom_level);
   EXPECT_FLOAT_EQ(old_zoom_level, zoom_controller->GetZoomLevel());
 }
+
+IN_PROC_BROWSER_TEST_F(ZoomControllerBrowserTest, OnPreferenceChanged) {
+  content::WebContents* web_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  double new_default_zoom_level = 1.0;
+  // Since this page uses the default zoom level, the changes to the default
+  // zoom level will change the zoom level for this web_contents.
+  ZoomController::ZoomChangedEventData zoom_change_data(
+      web_contents,
+      new_default_zoom_level,
+      new_default_zoom_level,
+      ZoomController::ZOOM_MODE_DEFAULT,
+      true);
+  ZoomChangedWatcher zoom_change_watcher(web_contents, zoom_change_data);
+  // TODO(wjmaclean): Convert this to call partition-specific zoom level prefs
+  // when they become available.
+  browser()->profile()->GetPrefs()->SetDouble(prefs::kDefaultZoomLevel,
+                                              new_default_zoom_level);
+  // Because this test relies on a round-trip IPC to/from the renderer process,
+  // we need to wait for it to propagate.
+  zoom_change_watcher.Wait();
+}