Bug 31740: Remove some unnecessary RemoteSettings instances

More concretely, SearchService.jsm 'hijack-blocklists' and
url-classifier-skip-urls.

Avoid creating instance for 'anti-tracking-url-decoration'.

If prefs are disabling their usage, avoid creating instances for
'cert-revocations' and 'intermediates'.

Do not ship JSON dumps for collections we do not expect to need. For
the ones in the 'main' bucket, this prevents them from being synced
unnecessarily (the code in remote-settings does so for collections
in the main bucket for which a dump or local data exists). For the
collections in the other buckets, we just save some size by not
shipping their dumps.

We also clear the collections database on the v2 -> v3 migration.

browser/components/search/SearchSERPTelemetry.jsm

@@ -96,13 +96,7 @@ class TelemetryHandler {
       return;
     }
 
-    this._telemetrySettings = RemoteSettings(TELEMETRY_SETTINGS_KEY);
     let rawProviderInfo = [];
-    try {
-      rawProviderInfo = await this._telemetrySettings.get();
-    } catch (ex) {
-      logConsole.error("Could not get settings:", ex);
-    }
 
     // Send the provider info to the child handler.
     this._contentHandler.init(rawProviderInfo);

netwerk/url-classifier/UrlClassifierFeatureBase.cpp

@@ -78,7 +78,7 @@ void UrlClassifierFeatureBase::InitializePreferences() {
 
   nsCOMPtr<nsIUrlClassifierExceptionListService> exceptionListService =
       do_GetService("@mozilla.org/url-classifier/exception-list-service;1");
-  if (NS_WARN_IF(!exceptionListService)) {
+  if (!exceptionListService) {
     return;
   }
 

netwerk/url-classifier/components.conf

@@ -13,10 +13,4 @@ Classes = [
         'constructor': 'mozilla::net::ChannelClassifierService::GetSingleton',
         'headers': ['mozilla/net/ChannelClassifierService.h'],
     },
-    {
-        'cid': '{b9f4fd03-9d87-4bfd-9958-85a821750ddc}',
-        'contract_ids': ['@mozilla.org/url-classifier/exception-list-service;1'],
-        'jsm': 'resource://gre/modules/UrlClassifierExceptionListService.jsm',
-        'constructor': 'UrlClassifierExceptionListService',
-    },
 ]

security/manager/ssl/RemoteSecuritySettings.jsm

@@ -249,6 +249,16 @@ var RemoteSecuritySettings = {
 
 class IntermediatePreloads {
   constructor() {
+    this.maybeInit();
+  }
+
+  maybeInit() {
+    if (
+      this.client ||
+      !Services.prefs.getBoolPref(INTERMEDIATES_ENABLED_PREF, true)
+    ) {
+      return;
+    }
     this.client = RemoteSettings("intermediates", {
       bucketName: SECURITY_STATE_BUCKET,
       signerName: SECURITY_STATE_SIGNER,
@@ -274,6 +284,7 @@ class IntermediatePreloads {
       );
       return;
     }
+    this.maybeInit();
 
     // Download attachments that are awaiting download, up to a max.
     const maxDownloadsPerRun = Services.prefs.getIntPref(
@@ -481,6 +492,16 @@ function compareFilters(filterA, filterB) {
 
 class CRLiteFilters {
   constructor() {
+    this.maybeInit();
+  }
+
+  maybeInit() {
+    if (
+      this.client ||
+      !Services.prefs.getBoolPref(CRLITE_FILTERS_ENABLED_PREF, true)
+    ) {
+      return;
+    }
     this.client = RemoteSettings("cert-revocations", {
       bucketName: SECURITY_STATE_BUCKET,
       signerName: SECURITY_STATE_SIGNER,
@@ -504,6 +525,8 @@ class CRLiteFilters {
       return;
     }
 
+    this.maybeInit();
+
     let hasPriorFilter = await hasPriorData(
       Ci.nsICertStorage.DATA_TYPE_CRLITE_FILTER_FULL
     );

services/settings/IDBHelpers.jsm

@@ -188,6 +188,10 @@ async function openIDB(allowUpgrades = true) {
         });
       }
       if (event.oldVersion < 3) {
+        // Clear existing stores for a fresh start
+        transaction.objectStore("records").clear();
+        transaction.objectStore("timestamps").clear();
+        transaction.objectStore("collections").clear();
         // Attachment store
         db.createObjectStore("attachments", {
           keyPath: ["cid", "attachmentId"],

services/settings/dumps/blocklists/moz.build

@@ -8,15 +8,11 @@ with Files("**"):
     BUG_COMPONENT = ("Toolkit", "Blocklist Implementation")
 
 # The addons blocklist is also in mobile/android/installer/package-manifest.in
-if CONFIG["MOZ_WIDGET_TOOLKIT"] == "android":
-    # Remove this once bug 1639050 is resolved.
-    FINAL_TARGET_FILES.defaults.settings.blocklists += ["addons.json"]
-else:
-    FINAL_TARGET_FILES.defaults.settings.blocklists += [
-        "addons-bloomfilters.json",
-        "gfx.json",
-        "plugins.json",
-    ]
+FINAL_TARGET_FILES.defaults.settings.blocklists += [
+    "addons-bloomfilters.json",
+    "gfx.json",
+    "plugins.json",
+]
 
 FINAL_TARGET_FILES.defaults.settings.blocklists["addons-bloomfilters"] += [
     "addons-bloomfilters/addons-mlbf.bin",

services/settings/dumps/main/moz.build

@@ -3,19 +3,11 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 FINAL_TARGET_FILES.defaults.settings.main += [
-    "anti-tracking-url-decoration.json",
-    "devtools-compatibility-browsers.json",
     "example.json",
     "hijack-blocklists.json",
     "language-dictionaries.json",
-    "password-recipes.json",
     "password-rules.json",
-    "search-config.json",
     "search-default-override-allowlist.json",
-    "search-telemetry-v2.json",
-    "sites-classification.json",
-    "top-sites.json",
-    "url-classifier-skip-urls.json",
     "websites-with-shared-credential-backends.json",
 ]
 

services/settings/dumps/security-state/moz.build

@@ -3,7 +3,6 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 FINAL_TARGET_FILES.defaults.settings["security-state"] += [
-    "intermediates.json",
     "onecrl.json",
 ]
 

toolkit/components/antitracking/antitracking.manifest

-category profile-after-change URLDecorationAnnotationsService @mozilla.org/tracking-url-decoration-service;1 process=main
+# category profile-after-change URLDecorationAnnotationsService @mozilla.org/tracking-url-decoration-service;1 process=main

toolkit/components/antitracking/components.conf

@@ -11,13 +11,6 @@ Classes = [
         'jsm': 'resource://gre/modules/TrackingDBService.jsm',
         'constructor': 'TrackingDBService',
     },
-    {
-        'cid': '{5874af6d-5719-4e1b-b155-ef4eae7fcb32}',
-        'contract_ids': ['@mozilla.org/tracking-url-decoration-service;1'],
-        'jsm': 'resource://gre/modules/URLDecorationAnnotationsService.jsm',
-        'constructor': 'URLDecorationAnnotationsService',
-        'processes': ProcessSelector.MAIN_PROCESS_ONLY,
-    },
     {
         'cid': '{90d1fd17-2018-4e16-b73c-a04a26fa6dd4}',
         'contract_ids': ['@mozilla.org/purge-tracker-service;1'],

toolkit/components/search/SearchService.jsm

@@ -247,8 +247,6 @@ SearchService.prototype = {
       // See if we have a settings file so we don't have to parse a bunch of XML.
       let settings = await this._settings.get();
 
-      this._setupRemoteSettings().catch(Cu.reportError);
-
       await this._loadEngines(settings);
 
       // If we've got this far, but the application is now shutting down,