Bug 1011738 - Theme support for b2g/gaia, Part 2 : stylesheet reloading r=bz,seth

content/base/public/nsIStyleSheetLinkingElement.h

@@ -12,8 +12,8 @@ class nsICSSLoaderObserver;
 class nsIURI;
 
 #define NS_ISTYLESHEETLINKINGELEMENT_IID          \
-{ 0xd753c84a, 0x17fd, 0x4d5f, \
- { 0xb2, 0xe9, 0x63, 0x52, 0x8c, 0x87, 0x99, 0x7a } }
+{ 0xe5855604, 0x8a9a, 0x4181, \
+ { 0xbe, 0x41, 0xdd, 0xf7, 0x08, 0x70, 0x3f, 0xbe } }
 
 namespace mozilla {
 class CSSStyleSheet;
@@ -60,10 +60,13 @@ public:
    *                          failure code will be returned.
    * @param [out] whether the sheet is an alternate sheet.  This value is only
    *              meaningful if aWillNotify is true.
+   * @param aForceUpdate whether we wand to force the update, flushing the
+   *                     cached version if any.
    */
   NS_IMETHOD UpdateStyleSheet(nsICSSLoaderObserver* aObserver,
                               bool *aWillNotify,
-                              bool *aIsAlternate) = 0;
+                              bool *aIsAlternate,
+                              bool aForceUpdate = false) = 0;
 
   /**
    * Tells this element whether to update the stylesheet when the

content/base/src/nsDocument.cpp

@@ -8873,7 +8873,7 @@ nsDocument::OnPageShow(bool aPersisted,
                         "chrome-page-shown" :
                         "content-page-shown",
                       nullptr);
-
+  os->AddObserver(this, "app-theme-changed", /* ownsWeak */ false);
 
   DispatchPageTransition(target, NS_LITERAL_STRING("pageshow"), aPersisted);
 }
@@ -8947,6 +8947,8 @@ nsDocument::OnPageHide(bool aPersisted,
                           "chrome-page-hidden" :
                           "content-page-hidden",
                         nullptr);
+
+    os->RemoveObserver(this, "app-theme-changed");
   }
 
   DispatchPageTransition(target, NS_LITERAL_STRING("pagehide"), aPersisted);
@@ -11656,10 +11658,57 @@ nsDocument::Observe(nsISupports *aSubject,
         NS_DispatchToMainThread(r);
       }
     }
+  } else if (strcmp("app-theme-changed", aTopic) == 0) {
+    if (!nsContentUtils::IsSystemPrincipal(NodePrincipal()) &&
+        !IsUnstyledDocument()) {
+      // We don't want to style the chrome window, only app ones.
+      OnAppThemeChanged();
+    }
   }
   return NS_OK;
 }
 
+void
+nsDocument::OnAppThemeChanged()
+{
+  // Bail out if there is no theme support set up properly.
+  auto themeOrigin = Preferences::GetString("b2g.theme.origin");
+  if (!themeOrigin || !Preferences::GetBool("dom.mozApps.themable")) {
+    return;
+  }
+
+  for (int32_t i = 0; i < GetNumberOfStyleSheets(); i++) {
+    nsRefPtr<CSSStyleSheet> sheet =  do_QueryObject(GetStyleSheetAt(i));
+    if (!sheet) {
+      continue;
+    }
+
+    nsINode* owningNode = sheet->GetOwnerNode();
+    if (!owningNode) {
+      continue;
+    }
+    // Get a DOM stylesheet link to check the href against the theme origin.
+    nsIURI* sheetURI = sheet->GetOriginalURI();
+    if (!sheetURI) {
+      continue;
+    }
+    nsAutoString sheetOrigin;
+    nsContentUtils::GetUTFOrigin(sheetURI, sheetOrigin);
+    if (!sheetOrigin.Equals(themeOrigin)) {
+      continue;
+    }
+
+    // Finally getting a Stylesheet link.
+    nsCOMPtr<nsIStyleSheetLinkingElement> link = do_QueryInterface(owningNode);
+    if (!link) {
+      continue;
+    }
+    bool willNotify;
+    bool isAlternate;
+    link->UpdateStyleSheet(nullptr, &willNotify, &isAlternate, true);
+  }
+}
+
 void
 nsDocument::RequestPointerLock(Element* aElement)
 {

content/base/src/nsDocument.h

@@ -937,6 +937,12 @@ public:
 
   virtual nsViewportInfo GetViewportInfo(const mozilla::ScreenIntSize& aDisplaySize) MOZ_OVERRIDE;
 
+  /**
+   * Called when an app-theme-changed observer notification is
+   * received by this document.
+   */
+  void OnAppThemeChanged();
+
 private:
   void AddOnDemandBuiltInUASheet(mozilla::CSSStyleSheet* aSheet);
   nsRadioGroupStruct* GetRadioGroupInternal(const nsAString& aName) const;

content/base/src/nsStyleLinkElement.cpp

@@ -201,10 +201,21 @@ uint32_t nsStyleLinkElement::ParseLinkTypes(const nsAString& aTypes, nsIPrincipa
 NS_IMETHODIMP
 nsStyleLinkElement::UpdateStyleSheet(nsICSSLoaderObserver* aObserver,
                                      bool* aWillNotify,
-                                     bool* aIsAlternate)
+                                     bool* aIsAlternate,
+                                     bool aForceReload)
 {
+  if (aForceReload) {
+    // We remove this stylesheet from the cache to load a new version.
+    nsCOMPtr<nsIContent> thisContent;
+    CallQueryInterface(this, getter_AddRefs(thisContent));
+    nsIDocument* doc = thisContent->GetCrossShadowCurrentDoc();
+    if (doc && doc->CSSLoader()->GetEnabled() &&
+        mStyleSheet && mStyleSheet->GetOriginalURI()) {
+      doc->CSSLoader()->ObsoleteSheet(mStyleSheet->GetOriginalURI());
+    }
+  }
   return DoUpdateStyleSheet(nullptr, nullptr, aObserver, aWillNotify,
-                            aIsAlternate, false);
+                            aIsAlternate, aForceReload);
 }
 
 nsresult

content/base/src/nsStyleLinkElement.h

@@ -45,7 +45,8 @@ public:
   NS_IMETHOD InitStyleLinkElement(bool aDontLoadStyle) MOZ_OVERRIDE;
   NS_IMETHOD UpdateStyleSheet(nsICSSLoaderObserver* aObserver,
                               bool* aWillNotify,
-                              bool* aIsAlternate) MOZ_OVERRIDE;
+                              bool* aIsAlternate,
+                              bool aForceReload) MOZ_OVERRIDE;
   NS_IMETHOD SetEnableUpdates(bool aEnableUpdates) MOZ_OVERRIDE;
   NS_IMETHOD GetCharset(nsAString& aCharset) MOZ_OVERRIDE;
 

image/src/imgLoader.cpp

@@ -858,7 +858,8 @@ NS_IMPL_ISUPPORTS(imgCacheObserver, nsIObserver)
 NS_IMETHODIMP
 imgCacheObserver::Observe(nsISupports* aSubject, const char* aTopic, const char16_t* aSomeData)
 {
-  if (strcmp(aTopic, "memory-pressure") == 0) {
+  if (strcmp(aTopic, "memory-pressure") == 0 ||
+      strcmp(aTopic, "app-theme-changed") == 0) {
     DiscardTracker::DiscardAll();
   }
   return NS_OK;
@@ -1015,8 +1016,10 @@ void imgLoader::GlobalInit()
   NS_ADDREF(gCacheObserver);
 
   nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
-  if (os)
+  if (os) {
     os->AddObserver(gCacheObserver, "memory-pressure", false);
+    os->AddObserver(gCacheObserver, "app-theme-changed", false);
+  }
 
   int32_t timeweight;
   nsresult rv = Preferences::GetInt("image.cache.timeweight", &timeweight);
@@ -1045,6 +1048,7 @@ nsresult imgLoader::InitCache()
     return NS_ERROR_FAILURE;
 
   os->AddObserver(this, "memory-pressure", false);
+  os->AddObserver(this, "app-theme-changed", false);
   os->AddObserver(this, "chrome-flush-skin-caches", false);
   os->AddObserver(this, "chrome-flush-caches", false);
   os->AddObserver(this, "last-pb-context-exited", false);
@@ -1085,6 +1089,9 @@ imgLoader::Observe(nsISupports* aSubject, const char* aTopic, const char16_t* aD
 
   } else if (strcmp(aTopic, "memory-pressure") == 0) {
     MinimizeCaches();
+  } else if (strcmp(aTopic, "app-theme-changed") == 0) {
+    ClearImageCache();
+    MinimizeCaches();
   } else if (strcmp(aTopic, "chrome-flush-skin-caches") == 0 ||
              strcmp(aTopic, "chrome-flush-caches") == 0) {
     MinimizeCaches();