Bug 1483440 - Part 1 - Remove purge-domain-data, add purge-sessionStorage notification. r=baku

The browser:purge-domain-data notification had two different intentions,
- to clear session store information and
- to clear all localStorage and sessionStorage
Firing the notification accomplished both at the same time, which from a
user perspective is of course totally not understandable. This commit
removes purge-domain-data in favor of the two distinct purge-localStorage and
purge-sessionStorage events. This gives callers more granular choice on
what they want to clear.

Differential Revision: https://phabricator.services.mozilla.com/D16460

--HG--
extra : moz-landing-system : lando

dom/storage/LocalStorageManager.cpp

@@ -395,6 +395,11 @@ nsresult LocalStorageManager::Observe(const char* aTopic,
     return NS_OK;
   }
 
+  if (!strcmp(aTopic, "browser:purge-sessionStorage")) {
+    // This is only meant for SessionStorageManager.
+    return NS_OK;
+  }
+
   // Clear from caches everything that has been stored
   // while in session-only mode
   if (!strcmp(aTopic, "session-only-cleared")) {
@@ -402,13 +407,6 @@ nsresult LocalStorageManager::Observe(const char* aTopic,
     return NS_OK;
   }
 
-  // Clear everything (including so and pb data) from caches and database
-  // for the gived domain and subdomains.
-  if (!strcmp(aTopic, "domain-data-cleared")) {
-    ClearCaches(LocalStorageCache::kUnloadComplete, pattern, aOriginScope);
-    return NS_OK;
-  }
-
   // Clear all private-browsing caches
   if (!strcmp(aTopic, "private-browsing-data-cleared")) {
     ClearCaches(LocalStorageCache::kUnloadPrivate, pattern, EmptyCString());

dom/storage/SessionStorageManager.cpp

@@ -243,8 +243,8 @@ nsresult SessionStorageManager::Observe(
   }
 
   // Clear everything (including so and pb data) from caches and database
-  // for the gived domain and subdomains.
-  if (!strcmp(aTopic, "domain-data-cleared")) {
+  // for the given domain and subdomains.
+  if (!strcmp(aTopic, "browser:purge-sessionStorage")) {
     ClearStorages(eAll, pattern, aOriginScope);
     return NS_OK;
   }

dom/storage/StorageObserver.cpp

@@ -59,10 +59,10 @@ nsresult StorageObserver::Init() {
   obs->AddObserver(sSelf, kStartupTopic, true);
   obs->AddObserver(sSelf, "cookie-changed", true);
   obs->AddObserver(sSelf, "perm-changed", true);
-  obs->AddObserver(sSelf, "browser:purge-domain-data", true);
   obs->AddObserver(sSelf, "last-pb-context-exited", true);
   obs->AddObserver(sSelf, "clear-origin-attributes-data", true);
   obs->AddObserver(sSelf, "extension:purge-localStorage", true);
+  obs->AddObserver(sSelf, "browser:purge-sessionStorage", true);
 
   // Shutdown
   obs->AddObserver(sSelf, "profile-after-change", true);
@@ -135,8 +135,8 @@ void StorageObserver::NoteBackgroundThread(nsIEventTarget* aBackgroundThread) {
   mBackgroundThread = aBackgroundThread;
 }
 
-nsresult StorageObserver::ClearMatchingOrigin(const char16_t* aData,
-                                              nsACString& aOriginScope) {
+nsresult StorageObserver::GetOriginScope(const char16_t* aData,
+                                         nsACString& aOriginScope) {
   nsresult rv;
 
   NS_ConvertUTF16toUTF8 domain(aData);
@@ -162,17 +162,6 @@ nsresult StorageObserver::ClearMatchingOrigin(const char16_t* aData,
     return rv;
   }
 
-  if (!NextGenLocalStorageEnabled()) {
-    if (XRE_IsParentProcess()) {
-      StorageDBChild* storageChild = StorageDBChild::GetOrCreate();
-      if (NS_WARN_IF(!storageChild)) {
-        return NS_ERROR_FAILURE;
-      }
-
-      storageChild->SendClearMatchingOrigin(originScope);
-    }
-  }
-
   aOriginScope = originScope;
   return NS_OK;
 }
@@ -309,11 +298,21 @@ StorageObserver::Observe(nsISupports* aSubject, const char* aTopic,
 
     if (aData) {
       nsCString originScope;
-      rv = ClearMatchingOrigin(aData, originScope);
+
+      rv = GetOriginScope(aData, originScope);
       if (NS_WARN_IF(NS_FAILED(rv))) {
         return rv;
       }
 
+      if (XRE_IsParentProcess()) {
+        StorageDBChild* storageChild = StorageDBChild::GetOrCreate();
+        if (NS_WARN_IF(!storageChild)) {
+          return NS_ERROR_FAILURE;
+        }
+
+        storageChild->SendClearMatchingOrigin(originScope);
+      }
+
       Notify(topic, EmptyString(), originScope);
     } else {
       StorageDBChild* storageChild = StorageDBChild::GetOrCreate();
@@ -333,16 +332,18 @@ StorageObserver::Observe(nsISupports* aSubject, const char* aTopic,
     return NS_OK;
   }
 
-  // Clear everything (including so and pb data) from caches and database
-  // for the given domain and subdomains.
-  if (!strcmp(aTopic, "browser:purge-domain-data")) {
-    nsCString originScope;
-    rv = ClearMatchingOrigin(aData, originScope);
-    if (NS_WARN_IF(NS_FAILED(rv))) {
-      return rv;
-    }
+  if (!strcmp(aTopic, "browser:purge-sessionStorage")) {
+    if (aData) {
+      nsCString originScope;
+      rv = GetOriginScope(aData, originScope);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return rv;
+      }
 
-    Notify("domain-data-cleared", EmptyString(), originScope);
+      Notify(aTopic, EmptyString(), originScope);
+    } else {
+      Notify(aTopic, EmptyString(), EmptyCString());
+    }
 
     return NS_OK;
   }

dom/storage/StorageObserver.h

@@ -53,7 +53,7 @@ class StorageObserver : public nsIObserver, public nsSupportsWeakReference {
  private:
   virtual ~StorageObserver() {}
 
-  nsresult ClearMatchingOrigin(const char16_t* aData, nsACString& aOriginScope);
+  nsresult GetOriginScope(const char16_t* aData, nsACString& aOriginScope);
 
   static void TestingPrefChanged(const char* aPrefName, void* aClosure);
 

dom/tests/mochitest/localstorage/localStorageCommon.js

@@ -102,7 +102,7 @@ function localStorageClearDomain(domain, callback)
     return;
   }
 
-  os().notifyObservers(null, "browser:purge-domain-data", domain);
+  os().notifyObservers(null, "extension:purge-localStorage", domain);
   SimpleTest.executeSoon(function () {
     callback();
   });