Bug 689058 - Implement document.mozFullScreenEnabled r=cpearce sr=roc

content/base/src/nsDocument.cpp

@@ -8660,6 +8660,38 @@ nsDocument::GetMozFullScreen(bool *aFullScreen)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsDocument::GetMozFullScreenEnabled(bool *aFullScreen)
+{
+  NS_ENSURE_ARG_POINTER(aFullScreen);
+  *aFullScreen = false;
+
+  if (!nsContentUtils::IsFullScreenApiEnabled()) {
+    return NS_OK;
+  }
+
+  // todo: Bug 684618 - Deny requests for DOM full-screen when windowed
+  // plugins are present.
+
+  // Ensure that all ancestor <iframe> elements have the mozallowfullscreen
+  // boolean attribute set.
+  nsINode* node = static_cast<nsINode*>(this);
+  do {
+    nsIContent* content = static_cast<nsIContent*>(node);
+    if (content->IsHTML(nsGkAtoms::iframe) &&
+        !content->HasAttr(kNameSpaceID_None, nsGkAtoms::mozallowfullscreen)) {
+      // The node requesting fullscreen, or one of its crossdoc ancestors,
+      // is an iframe which doesn't have the "mozalllowfullscreen" attribute.
+      // This request is not authorized by the parent document.
+      return NS_OK;
+    }
+    node = nsContentUtils::GetCrossDocParentNode(node);
+  } while (node);
+
+  *aFullScreen = true;
+  return NS_OK;
+}
+
 PRInt64
 nsDocument::SizeOf() const
 {

content/html/content/src/nsGenericHTMLElement.cpp

@@ -3419,28 +3419,20 @@ nsresult nsGenericHTMLElement::MozRequestFullScreen()
   // This stops the full-screen from being abused similar to the popups of old,
   // and it also makes it harder for bad guys' script to go full-screen and
   // spoof the browser chrome/window and phish logins etc.
-  if (!nsContentUtils::IsFullScreenApiEnabled() ||
-      !nsContentUtils::IsRequestFullScreenAllowed()) {
+  if (!nsContentUtils::IsRequestFullScreenAllowed()) {
     return NS_OK;
   }
 
-  // Ensure that all ancestor <iframe> elements have the mozallowfullscreen
-  // boolean attribute set.
-  nsINode* node = static_cast<nsINode*>(this);
-  do {
-    nsIContent* content = static_cast<nsIContent*>(node);
-    if (content->IsHTML(nsGkAtoms::iframe) &&
-        !content->HasAttr(kNameSpaceID_None, nsGkAtoms::mozallowfullscreen)) {
-      // The node requesting fullscreen, or one of its crossdoc ancestors,
-      // is an iframe which doesn't have the "mozalllowfullscreen" attribute.
-      // This request is not authorized by the parent document.
-      return NS_OK;
-    }
-    node = nsContentUtils::GetCrossDocParentNode(node);
-  } while (node);
-
   nsIDocument* doc = GetOwnerDoc();
   NS_ENSURE_STATE(doc);
+  nsCOMPtr<nsIDOMDocument> domDocument(do_QueryInterface(doc));
+  NS_ENSURE_STATE(domDocument);
+  bool fullScreenEnabled;
+  domDocument->GetMozFullScreenEnabled(&fullScreenEnabled);
+  if (!fullScreenEnabled) {
+    return NS_OK;
+  }
+
   doc->RequestFullScreen(this);
 #ifdef DEBUG
   nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(doc->GetWindow());
@@ -3448,7 +3440,6 @@ nsresult nsGenericHTMLElement::MozRequestFullScreen()
   bool fullscreen;
   window->GetFullScreen(&fullscreen);
   NS_ASSERTION(fullscreen, "Windows should report fullscreen");
-  nsCOMPtr<nsIDOMDocument> domDocument(do_QueryInterface(doc));
   domDocument->GetMozFullScreen(&fullscreen);
   NS_ASSERTION(fullscreen, "Document should report fullscreen");
   NS_ASSERTION(doc->IsFullScreenDoc(), "Should be in full screen state!");

content/html/content/test/file_fullscreen-api.html

@@ -140,7 +140,23 @@ function fullScreenChange(event) {
       break;
     }
     case 7: {
-      ok(!document.mozFullScreen, "Should have left full-screen mode (last time).");      
+      ok(!document.mozFullScreen, "Should have left full-screen mode (last time).");
+
+      SpecialPowers.setBoolPref("full-screen-api.enabled", false);
+      is(document.mozFullScreenEnabled, false, "document.mozFullScreenEnabled should be false if full-screen-api.enabled is false");
+      document.body.mozRequestFullScreen();
+      ok(!document.mozFullScreen, "Should still be in normal mode, because pref is not enabled.");
+
+      SpecialPowers.setBoolPref("full-screen-api.enabled", true);
+      is(document.mozFullScreenEnabled, true, "document.mozFullScreenEnabled should be true if full-screen-api.enabled is true");
+
+      iframe = document.createElement("iframe");
+      document.body.appendChild(iframe);
+      iframe.src = iframeContents;
+      ok(!document.mozFullScreen, "Should still be in normal mode, because iframe did not have mozallowfullscreen attribute.");
+      document.body.removeChild(iframe);
+      iframe = null;
+
       // Set timeout for calling finish(), so that any pending "mozfullscreenchange" events
       // would have a chance to fire.
       setTimeout(function(){opener.apiTestFinished();}, 0);

dom/interfaces/core/nsIDOMDocument.idl

@@ -67,7 +67,7 @@ interface nsIDOMCaretPosition;
  * http://dvcs.w3.org/hg/domcore/raw-file/tip/Overview.html
  */
 
-[scriptable, uuid(489faaa9-c54e-466c-8164-9a5fcc3a7052)]
+[scriptable, uuid(86bdbe61-760c-4982-a822-c6a0df63b8d2)]
 interface nsIDOMDocument : nsIDOMNode
 {
   readonly attribute nsIDOMDocumentType         doctype;
@@ -398,6 +398,15 @@ interface nsIDOMDocument : nsIDOMNode
    */
   readonly attribute boolean mozFullScreen;  
 
+  /**
+   * Denotes whether the full-screen-api.enabled is true, no windowed
+   * plugins are present, and all ancestor documents have the
+   * mozallowfullscreen attribute set.
+   *
+   * @see <https://wiki.mozilla.org/index.php?title=Gecko:FullScreenAPI>
+   */
+  readonly attribute boolean mozFullScreenEnabled;
+
   /**
    * Inline event handler for readystatechange events.
    */