Bug 777672 - [b2g] |body { overflow: hidden }| do not hide scrollbars (css part). r=fabrice

b2g/chrome/content/content.css

@@ -11,23 +11,18 @@ xul|window xul|scrollbar {
 }
 
 html xul|scrollbar {
-  display: block;
-}
-
-xul|scrollbar[orient="vertical"] {
   -moz-appearance: none !important;
   position: relative;
-  margin-left: -8px;
-  min-width: 8px;
-  max-width: 8px;
   background-color: transparent !important;
   background-image: none !important;
   border: 0px solid transparent !important;
+  z-index: 2147483647;
 }
 
-xul|scrollbar[orient="vertical"]:-moz-locale-dir(rtl) {
-  margin-left: 2px;
-  margin-right: -10px;
+xul|scrollbar[orient="vertical"] {
+  -moz-margin-start: -8px;
+  min-width: 8px;
+  max-width: 8px;
 }
 
 xul|scrollbar[orient="vertical"] xul|thumb {
@@ -36,14 +31,9 @@ xul|scrollbar[orient="vertical"] xul|thumb {
 }
 
 xul|scrollbar[orient="horizontal"] {
-  -moz-appearance: none !important;
-  position: relative;
+  margin-top: -8px;
   min-height: 8px;
   max-height: 8px;
-  margin-top: -8px;
-  background-color: transparent !important;
-  background-image: none !important;
-  border: 0px solid transparent !important;
 }
 
 xul|scrollbar[orient="horizontal"] xul|thumb {
@@ -51,9 +41,8 @@ xul|scrollbar[orient="horizontal"] xul|thumb {
   min-height: 6px !important;
 }
 
-xul|scrollbox {
-  overflow-y: scroll;
-  overflow-x: scroll;
+xul|scrollbar[disabled] {
+  display: none;
 }
 
 xul|scrollbarbutton {

dom/browser-element/BrowserElementChild.js

@@ -21,7 +21,7 @@ let whitelistedEvents = [
 ];
 
 function debug(msg) {
-  //dump("BrowserElementChild - " + msg + "\n");
+  dump("BrowserElementChild - " + msg + "\n");
 }
 
 function sendAsyncMsg(msg, data) {

dom/browser-element/BrowserElementScrolling.js

@@ -112,6 +112,13 @@ const ContentPanning = {
   },
 
   getPannable: function cp_getPannable(node) {
+debug('getPannable');
+let scrollable = docShell.QueryInterface(Ci.nsIScrollable);
+
+let canHaveHorizontal = {};
+let canHaveVertical = {};
+scrollable.getScrollbarVisibility(canHaveHorizontal, canHaveVertical);
+debug('horizontal: ' + canHaveHorizontal.value + ' vertical: ' + canHaveVertical.value);
     if (!(node instanceof Ci.nsIDOMHTMLElement) || node.tagName == 'HTML')
       return [null, null];
 
@@ -129,8 +136,10 @@ const ContentPanning = {
                     rect.width < node.scrollWidth));
 
       let isScroll = (overflow.indexOf('scroll') != -1);
-      if (isScroll || isAuto)
+      if (isScroll || isAuto) {
+        debug(node);
         return [node, this._generateCallback(node)];
+      }
 
       node = node.parentNode;
     }