Refresh nsStringBundleService and nsHttpHandler when the browser locale is changed

intl/strres/nsStringBundle.cpp

@@ -25,6 +25,7 @@
 #include "nsIErrorService.h"
 #include "nsICategoryManager.h"
 #include "nsContentUtils.h"
+#include "mozilla/Preferences.h"
 
 // for async loading
 #ifdef ASYNC_LOADING
@@ -32,6 +33,9 @@
 #include "nsIStringStream.h"
 #endif
 
+#define STR_HELPER(x) #x
+#define STR(x) STR_HELPER(x)
+
 using namespace mozilla;
 
 static NS_DEFINE_CID(kErrorServiceCID, NS_ERRORSERVICE_CID);
@@ -529,6 +533,8 @@ nsStringBundleService::Init()
     os->AddObserver(this, "profile-do-change", true);
     os->AddObserver(this, "chrome-flush-caches", true);
     os->AddObserver(this, "xpcom-category-entry-added", true);
+    os->AddObserver(this, "selected-locale-has-changed", true);
+    os->AddObserver(this, "final-ui-startup", true);
   }
 
   // instantiate the override service, if there is any.
@@ -550,6 +556,19 @@ nsStringBundleService::Observe(nsISupports* aSubject,
   {
     flushBundleCache();
   }
+  else if (strcmp("selected-locale-has-changed", aTopic) == 0)
+  {
+    flushBundleCache();
+    notifyBundlesFlushed();
+  }
+  else if (strcmp("final-ui-startup", aTopic) == 0)
+  {
+    nsAdoptingCString ualocale = Preferences::GetCString("general.useragent.locale");
+    if (!ualocale.EqualsLiteral(STR(MOZ_UI_LOCALE))) {
+      flushBundleCache();
+      notifyBundlesFlushed();
+    }
+  }
   else if (strcmp("xpcom-category-entry-added", aTopic) == 0 &&
            NS_LITERAL_STRING("xpcom-autoregistration").Equals(aSomeData))
   {
@@ -559,6 +578,14 @@ nsStringBundleService::Observe(nsISupports* aSubject,
   return NS_OK;
 }
 
+void
+nsStringBundleService::notifyBundlesFlushed()
+{
+  nsCOMPtr<nsIObserverService> obsSvc = mozilla::services::GetObserverService();
+  NS_ASSERTION(obsSvc, "Couldn't get observer service.");
+  obsSvc->NotifyObservers(nullptr, "string-bundles-have-flushed", nullptr);
+}
+
 void
 nsStringBundleService::flushBundleCache()
 {

intl/strres/nsStringBundleService.h

@@ -43,6 +43,8 @@ private:
 
   void flushBundleCache();
 
+  void notifyBundlesFlushed();
+
   bundleCacheEntry_t *insertIntoCache(already_AddRefed<nsIStringBundle> aBundle,
                                       nsCString &aHashKey);
 

netwerk/protocol/http/nsHttpHandler.cpp

@@ -203,6 +203,7 @@ nsHttpHandler::nsHttpHandler()
     , mCompatFirefoxEnabled(false)
     , mCompatFirefoxVersion("52.9")
     , mUserAgentIsDirty(true)
+    , mAcceptLanguagesIsDirty(true)
     , mPromptTempRedirect(true)
     , mEnablePersistentHttpsCaching(false)
     , mDoNotTrackEnabled(false)
@@ -419,6 +420,7 @@ nsHttpHandler::Init()
         obsService->AddObserver(this, "browser:purge-session-history", true);
         obsService->AddObserver(this, NS_NETWORK_LINK_TOPIC, true);
         obsService->AddObserver(this, "application-background", true);
+        obsService->AddObserver(this, "string-bundles-have-flushed", true);
     }
 
     MakeNewRequestTokenBucket();
@@ -489,8 +491,13 @@ nsHttpHandler::AddStandardRequestHeaders(nsHttpRequestHead *request, bool isSecu
 
     // Add the "Accept-Language" header.  This header is also exposed to the
     // service worker.
+    if (mAcceptLanguagesIsDirty) {
+        rv = SetAcceptLanguages();
+        MOZ_ASSERT(NS_SUCCEEDED(rv));
+    }
+
+    // Add the "Accept-Language" header
     if (!mAcceptLanguages.IsEmpty()) {
-        // Add the "Accept-Language" header
         rv = request->SetHeader(nsHttp::Accept_Language, mAcceptLanguages,
                                 false,
                                 nsHttpHeaderArray::eVarietyRequestOverride);
@@ -1511,16 +1518,10 @@ nsHttpHandler::PrefsChanged(nsIPrefBranch *prefs, const char *pref)
     //
 
     if (PREF_CHANGED(INTL_ACCEPT_LANGUAGES)) {
-        nsCOMPtr<nsIPrefLocalizedString> pls;
-        prefs->GetComplexValue(INTL_ACCEPT_LANGUAGES,
-                                NS_GET_IID(nsIPrefLocalizedString),
-                                getter_AddRefs(pls));
-        if (pls) {
-            nsXPIDLString uval;
-            pls->ToString(getter_Copies(uval));
-            if (uval)
-                SetAcceptLanguages(NS_ConvertUTF16toUTF8(uval).get());
-        }
+        // We don't want to set the new accept languages here since
+        // this pref is a complex type and it may be racy with flushing
+        // string resources.
+        mAcceptLanguagesIsDirty = true;
     }
 
     //
@@ -1897,12 +1898,18 @@ PrepareAcceptLanguages(const char *i_AcceptLanguages, nsACString &o_AcceptLangua
 }
 
 nsresult
-nsHttpHandler::SetAcceptLanguages(const char *aAcceptLanguages)
+nsHttpHandler::SetAcceptLanguages()
 {
+    mAcceptLanguagesIsDirty = false;
+
+    const nsAdoptingCString& acceptLanguages =
+        Preferences::GetLocalizedCString(INTL_ACCEPT_LANGUAGES);
+
     nsAutoCString buf;
-    nsresult rv = PrepareAcceptLanguages(aAcceptLanguages, buf);
-    if (NS_SUCCEEDED(rv))
+    nsresult rv = PrepareAcceptLanguages(acceptLanguages.get(), buf);
+    if (NS_SUCCEEDED(rv)) {
         mAcceptLanguages.Assign(buf);
+    }
     return rv;
 }
 
@@ -2233,6 +2240,8 @@ nsHttpHandler::Observe(nsISupports *subject,
         if (mConnMgr) {
             mConnMgr->DoShiftReloadConnectionCleanup(nullptr);
         }
+    } else if (!strcmp(topic, "string-bundles-have-flushed")) {
+        mAcceptLanguagesIsDirty = true;
     }
 
     return NS_OK;

netwerk/protocol/http/nsHttpHandler.h

@@ -384,7 +384,7 @@ private:
     void     PrefsChanged(nsIPrefBranch *prefs, const char *pref);
 
     nsresult SetAccept(const char *);
-    nsresult SetAcceptLanguages(const char *);
+    nsresult SetAcceptLanguages();
     nsresult SetAcceptEncodings(const char *, bool mIsSecure);
 
     nsresult InitConnectionMgr();
@@ -491,6 +491,7 @@ private:
     nsCString      mUserAgent;
     nsXPIDLCString mUserAgentOverride;
     bool           mUserAgentIsDirty; // true if mUserAgent should be rebuilt
+    bool           mAcceptLanguagesIsDirty;
 
 
     bool           mPromptTempRedirect;