Introduce ChromeZoomLevelPref, make zoom level prefs independent of profile prefs.

chrome/browser/profiles/host_zoom_map_browsertest.cc

Index: chrome/browser/profiles/host_zoom_map_browsertest.cc
diff --git a/chrome/browser/profiles/host_zoom_map_browsertest.cc b/chrome/browser/profiles/host_zoom_map_browsertest.cc
index e14a579048bbc586f142f9d74482c5069cd71ffa..cd4c30fc4af2e5a177cfa590628d82ea8f0bae23 100644
--- a/chrome/browser/profiles/host_zoom_map_browsertest.cc
+++ b/chrome/browser/profiles/host_zoom_map_browsertest.cc
@@ -75,7 +75,7 @@ class HostZoomMapBrowserTest : public InProcessBrowserTest {
 
  protected:
   void SetDefaultZoomLevel(double level) {
-    browser()->profile()->GetPrefs()->SetDouble(
+    browser()->profile()->GetZoomLevelPrefs()->SetDouble(
         prefs::kDefaultZoomLevel, level);
   }
 
@@ -102,7 +102,7 @@ class HostZoomMapBrowserTest : public InProcessBrowserTest {
   }
 
   std::vector<std::string> GetHostsWithZoomLevelsFromPrefs() {
-    PrefService* prefs = browser()->profile()->GetPrefs();
+    PrefService* prefs = browser()->profile()->GetZoomLevelPrefs();
     const base::DictionaryValue* values =
         prefs->GetDictionary(prefs::kPerHostZoomLevels);
     std::vector<std::string> results;
@@ -137,35 +137,50 @@ class HostZoomMapBrowserTest : public InProcessBrowserTest {
   DISALLOW_COPY_AND_ASSIGN(HostZoomMapBrowserTest);
 };
 
-class HostZoomMapSanitizationBrowserTest : public HostZoomMapBrowserTest {
+class HostZoomMapBrowserTestWithPrefs : public HostZoomMapBrowserTest {
  public:
-  HostZoomMapSanitizationBrowserTest() {}
+  HostZoomMapBrowserTestWithPrefs() {}
+
+ protected:
+  std::string prefs_data_;
+  std::string prefs_filename_;
 
  private:
   // InProcessBrowserTest:
   virtual bool SetUpUserDataDirectory() OVERRIDE {
-    // Zoom-related preferences demonstrating the two problems that could be
-    // caused by the bug. They incorrectly contain a per-host zoom level for the
-    // empty host; and a value for 'host1' that only differs from the default by
-    // epsilon. Neither should have been persisted.
-    const char kBrokenPrefs[] =
-        "{'profile': {"
-        "   'default_zoom_level': 1.2,"
-        "   'per_host_zoom_levels': {'': 1.1, 'host1': 1.20001, 'host2': 1.3}"
-        "}}";
-    std::string broken_prefs(kBrokenPrefs);
-    std::replace(broken_prefs.begin(), broken_prefs.end(), '\'', '\"');
+    std::replace(prefs_data_.begin(), prefs_data_.end(), '\'', '\"');
 
     base::FilePath user_data_directory, path_to_prefs;
     PathService::Get(chrome::DIR_USER_DATA, &user_data_directory);
     path_to_prefs = user_data_directory
         .AppendASCII(TestingProfile::kTestUserProfileDir)
-        .Append(chrome::kPreferencesFilename);
+        .Append(prefs_filename_);
     base::CreateDirectory(path_to_prefs.DirName());
-    base::WriteFile(path_to_prefs, broken_prefs.c_str(), broken_prefs.size());
+    base::WriteFile(
+        path_to_prefs, prefs_data_.c_str(), prefs_data_.size());
     return true;
   }
 
+  DISALLOW_COPY_AND_ASSIGN(HostZoomMapBrowserTestWithPrefs);
+};
+
+class HostZoomMapSanitizationBrowserTest
+    : public HostZoomMapBrowserTestWithPrefs {
+ public:
+  HostZoomMapSanitizationBrowserTest() {
+    // Zoom-related preferences demonstrating the two problems that could be
+    // caused by the bug. They incorrectly contain a per-host zoom level for the
+    // empty host; and a value for 'host1' that only differs from the default by
+    // epsilon. Neither should have been persisted.
+    prefs_data_ =
+        "{'partition': {"
+        "   'default_zoom_level': 1.2,"
+        "   'per_host_zoom_levels': {'': 1.1, 'host1': 1.20001, 'host2': 1.3}"
+        "}}";
+    prefs_filename_ = chrome::kZoomLevelPreferencesFilename;
+  }
+
+ private:
   DISALLOW_COPY_AND_ASSIGN(HostZoomMapSanitizationBrowserTest);
 };
 
@@ -216,3 +231,87 @@ IN_PROC_BROWSER_TEST_F(HostZoomMapSanitizationBrowserTest, ClearOnStartup) {
   EXPECT_THAT(GetHostsWithZoomLevels(), testing::ElementsAre("host2"));
   EXPECT_THAT(GetHostsWithZoomLevelsFromPrefs(), testing::ElementsAre("host2"));
 }
+
+class HostZoomMapMigrationBrowserTest : public HostZoomMapBrowserTestWithPrefs {
+ public:
+  HostZoomMapMigrationBrowserTest(): kOriginalDefaultZoomLevel(1.2) {
+    // In this case we migrate the zoom level data from the profile prefs.
+    prefs_data_ =
+        "{'profile': {"
+        "   'default_zoom_level': 1.2,"
+        "   'per_host_zoom_levels': {'': 1.1, 'host1': 1.20001, 'host2': 1.3}"
+        "}}";
+    prefs_filename_ = chrome::kPreferencesFilename;
+  }
+
+  const double kOriginalDefaultZoomLevel;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(HostZoomMapMigrationBrowserTest);
+};
+
+// This test is the same as HostZoomMapSanitizationBrowserTest, except that the
+// zoom level data is loaded from the profile prefs, transfered to the
+// zoom-level prefs, and we verify that the profile zoom level prefs are
+// erased in the process. We also test that changes to the host zoom map and the
+// default zoom level don't propagate back to the profile prefs.
+IN_PROC_BROWSER_TEST_F(HostZoomMapMigrationBrowserTest,
+                       MigrateProfileZoomPreferences) {
+  EXPECT_THAT(GetHostsWithZoomLevels(), testing::ElementsAre("host2"));
+  EXPECT_THAT(GetHostsWithZoomLevelsFromPrefs(), testing::ElementsAre("host2"));
+
+  PrefService* profile_prefs =
+      browser()->profile()->GetPrefs();
+  PrefService* zoom_level_prefs = browser()->profile()->GetZoomLevelPrefs();
+  // Make sure that the profile pref for default zoom level has been set to
+  // its default value of 0.0.
+  EXPECT_EQ(0.0, profile_prefs->GetDouble(prefs::kProfileDefaultZoomLevel));
+  EXPECT_EQ(kOriginalDefaultZoomLevel,
+            zoom_level_prefs->GetDouble(prefs::kDefaultZoomLevel));
+
+  // Make sure that the profile prefs for per-host zoom levels are erased.
+  {
+    const base::DictionaryValue* profile_host_zoom_dictionary =
+        profile_prefs->GetDictionary(prefs::kProfilePerHostZoomLevels);
+    EXPECT_EQ(0UL, profile_host_zoom_dictionary->size());
+  }
+
+  ZoomLevelChangeObserver observer(browser()->profile());
+  content::HostZoomMap* host_zoom_map = static_cast<content::HostZoomMap*>(
+      content::HostZoomMap::GetDefaultForBrowserContext(
+          browser()->profile()));
+
+  // Make sure that a change to a host zoom level doesn't propagate to the
+  // profile prefs.
+  std::string host3("host3");
+  host_zoom_map->SetZoomLevelForHost(host3, 1.3);
+  observer.BlockUntilZoomLevelForHostHasChanged(host3);
+  EXPECT_THAT(GetHostsWithZoomLevelsFromPrefs(),
+              testing::ElementsAre("host2", host3));
+  {
+    const base::DictionaryValue* profile_host_zoom_dictionary =
+        profile_prefs->GetDictionary(prefs::kProfilePerHostZoomLevels);
+    EXPECT_EQ(0UL, profile_host_zoom_dictionary->size());
+  }
+
+  // Make sure a change to the default zoom level doesn't propagate to the
+  // profile prefs.
+
+  // First, we need a host at the default zoom level to respond when the
+  // default zoom level changes.
+  const double kNewDefaultZoomLevel = 1.5;
+  GURL test_url = ConstructTestServerURL("http://host4:%d/");
+  ui_test_utils::NavigateToURL(browser(), test_url);
+  EXPECT_TRUE(content::ZoomValuesEqual(kOriginalDefaultZoomLevel,
+                                       GetZoomLevel(test_url)));
+
+  // Change the default zoom level and observe.
+  zoom_level_prefs->SetDouble(prefs::kDefaultZoomLevel, kNewDefaultZoomLevel);
+  observer.BlockUntilZoomLevelForHostHasChanged(test_url.host());
+  EXPECT_TRUE(
+      content::ZoomValuesEqual(kNewDefaultZoomLevel, GetZoomLevel(test_url)));
+  EXPECT_EQ(kNewDefaultZoomLevel,
+            zoom_level_prefs->GetDouble(prefs::kDefaultZoomLevel));
+  EXPECT_EQ(0.0, profile_prefs->GetDouble(prefs::kProfileDefaultZoomLevel));
+}
+