Add a policy and pref to control whether deleting browsing and download history is allowed.

The policy is currently disabled (by saying that it is supported on no platforms), pending a UI treatment that allows users to know when deleting browsing history is prohibited.

TBR=rlp@chromium.org

BUG=175419

Review URL: https://chromiumcodereview.appspot.com/12209091

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182233 0039d316-1c4b-4281-b951-d872f2087c98

chrome/app/policy/policy_templates.json

@@ -112,7 +112,7 @@
 #   persistent IDs for all fields (but not for groups!) are needed. These are
 #   specified by the 'id' keys of each policy. NEVER CHANGE EXISTING IDs,
 #   because doing so would break the deployed wire format!
-#   For your editing convenience: highest ID currently used: 186
+#   For your editing convenience: highest ID currently used: 187
 #
 # Placeholders:
 #   The following placeholder strings are automatically substituted:
@@ -436,6 +436,31 @@
 
       If this setting is disabled or not set, browsing history is saved.''',
     },
+    {
+      'name': 'AllowDeletingBrowserHistory',
+      'future': True,
+      'type': 'main',
+      'schema': { 'type': 'boolean' },
+      # TODO(pamg): Restore the correct 'supported' line when the UI properly
+      # shows that deleting browser history is disabled. Also fix the 'os' line
+      # in policy_test_cases.json.
+      # 'supported_on': ['chrome.*:27-', 'chrome_os:0.27-'],
+      'supported_on': [],
+      'features': {
+        'dynamic_refresh': True,
+        'per_profile': True,
+      },
+      'example_value': True,
+      'id': 187,
+      'caption': '''Enable deleting browser and download history''',
+      'desc': '''Enables deleting browser history and download history in <ph name="PRODUCT_NAME">$<ex>Google Chrome</ex></ph> and prevents users from changing this setting.
+
+      Note that even with this policy disabled, the browsing and download history are not guaranteed to be retained: users may be able to edit or delete the history database files directly, and the browser itself may expire or archive any or all history items at any time.
+
+      If this setting is enabled or not set, browsing and download history can be deleted.
+
+      If this setting is disabled, browsing and download history cannot be deleted.''',
+    },
     {
       'name': 'RemoteAccess',
       'type': 'group',

chrome/browser/policy/configuration_policy_handler_list.cc

@@ -106,6 +106,9 @@ const PolicyToPreferenceMapEntry kSimplePolicyMap[] = {
   { key::kSavingBrowserHistoryDisabled,
     prefs::kSavingBrowserHistoryDisabled,
     Value::TYPE_BOOLEAN },
+  { key::kAllowDeletingBrowserHistory,
+    prefs::kAllowDeletingBrowserHistory,
+    Value::TYPE_BOOLEAN },
   { key::kDeveloperToolsDisabled,
     prefs::kDevToolsDisabled,
     Value::TYPE_BOOLEAN },

chrome/browser/profiles/profile_impl.cc

@@ -276,6 +276,9 @@ void ProfileImpl::RegisterUserPrefs(PrefRegistrySyncable* registry) {
   registry->RegisterBooleanPref(prefs::kSavingBrowserHistoryDisabled,
                                 false,
                                 PrefRegistrySyncable::UNSYNCABLE_PREF);
+  registry->RegisterBooleanPref(prefs::kAllowDeletingBrowserHistory,
+                                true,
+                                PrefRegistrySyncable::UNSYNCABLE_PREF);
   registry->RegisterBooleanPref(prefs::kForceSafeSearch,
                                 false,
                                 PrefRegistrySyncable::UNSYNCABLE_PREF);

chrome/common/pref_names.cc

@@ -921,6 +921,10 @@ const char kSpeechRecognitionTrayNotificationShownContexts[] =
 // Boolean controlling whether history saving is disabled.
 const char kSavingBrowserHistoryDisabled[] = "history.saving_disabled";
 
+// Boolean controlling whether deleting browsing and download history is
+// permitted.
+const char kAllowDeletingBrowserHistory[] = "history.deleting_enabled";
+
 // Boolean controlling whether SafeSearch is mandatory for Google Web Searches.
 const char kForceSafeSearch[] = "settings.force_safesearch";
 

chrome/common/pref_names.h

@@ -326,6 +326,7 @@ extern const char kSpeechRecognitionTrayNotificationShownContexts[];
 extern const char kEnabledLabsExperiments[];
 extern const char kEnableAutoSpellCorrect[];
 extern const char kSavingBrowserHistoryDisabled[];
+extern const char kAllowDeletingBrowserHistory[];
 extern const char kForceSafeSearch[];
 extern const char kDeleteTimePeriod[];
 extern const char kLastClearBrowsingDataTime[];

chrome/test/data/policy/policy_test_cases.json

@@ -172,6 +172,14 @@
     ]
   },
 
+  "AllowDeletingBrowserHistory": {
+    "os": [],
+    "test_policy": { "AllowDeletingBrowserHistory": false },
+    "pref_mappings": [
+      { "pref": "history.deleting_enabled" }
+    ]
+  },
+
   "RemoteAccessClientFirewallTraversal": {
   },