Allow scrollbars without categories.

core/inject.js

@@ -117,14 +117,9 @@ Blockly.parseOptions_ = function(options) {
       hasDisable = hasCategories;
     }
   }
-  if (tree && !hasCategories) {
-    // Scrollbars are not compatible with a non-flyout toolbox.
-    var hasScrollbars = false;
-  } else {
-    var hasScrollbars = options['scrollbars'];
-    if (hasScrollbars === undefined) {
-      hasScrollbars = true;
-    }
+  var hasScrollbars = options['scrollbars'];
+  if (hasScrollbars === undefined) {
+    hasScrollbars = hasCategories;
   }
   var hasSounds = options['sounds'];
   if (hasSounds === undefined) {
@@ -287,42 +282,44 @@ Blockly.createDom_ = function(container) {
       flyout.autoClose = false;
       // Insert the flyout behind the workspace so that blocks appear on top.
       goog.dom.insertSiblingBefore(flyoutSvg, Blockly.mainWorkspace.svgGroup_);
+    }
+    if (!Blockly.hasScrollbars) {
       var workspaceChanged = function() {
         if (Blockly.Block.dragMode_ == 0) {
           var metrics = Blockly.mainWorkspace.getMetrics();
-          if (metrics.contentTop < 0 ||
+          var edgeLeft = metrics.viewLeft + metrics.absoluteLeft;
+          var edgeTop = metrics.viewTop + metrics.absoluteTop;
+          if (metrics.contentTop < edgeTop ||
               metrics.contentTop + metrics.contentHeight >
-              metrics.viewHeight + metrics.viewTop ||
-              metrics.contentLeft < (Blockly.RTL ? metrics.viewLeft : 0) ||
+              metrics.viewHeight + edgeTop ||
+              metrics.contentLeft <
+                  (Blockly.RTL ? metrics.viewLeft : edgeLeft) ||
               metrics.contentLeft + metrics.contentWidth > (Blockly.RTL ?
-                  metrics.viewWidth :
-                  metrics.viewWidth + metrics.viewLeft)) {
-            // One or more blocks is out of bounds.  Bump them back in.
+                  metrics.viewWidth : metrics.viewWidth + edgeLeft)) {
+            // One or more blocks may be out of bounds.  Bump them back in.
             var MARGIN = 25;
             var blocks = Blockly.mainWorkspace.getTopBlocks(false);
             for (var b = 0, block; block = blocks[b]; b++) {
               var blockXY = block.getRelativeToSurfaceXY();
               var blockHW = block.getHeightWidth();
               // Bump any block that's above the top back inside.
-              var overflow = metrics.viewTop + MARGIN - blockHW.height -
-                  blockXY.y;
+              var overflow = edgeTop + MARGIN - blockHW.height - blockXY.y;
               if (overflow > 0) {
                 block.moveBy(0, overflow);
               }
               // Bump any block that's below the bottom back inside.
-              var overflow = metrics.viewTop + metrics.viewHeight - MARGIN -
-                  blockXY.y;
+              var overflow = edgeTop + metrics.viewHeight - MARGIN - blockXY.y;
               if (overflow < 0) {
                 block.moveBy(0, overflow);
               }
               // Bump any block that's off the left back inside.
-              var overflow = MARGIN + metrics.viewLeft - blockXY.x -
-                  (Blockly.RTL ? 0 : blockHW.width);
+              var overflow = MARGIN + edgeLeft -
+                  blockXY.x - (Blockly.RTL ? 0 : blockHW.width);
               if (overflow > 0) {
                 block.moveBy(overflow, 0);
               }
               // Bump any block that's off the right back inside.
-              var overflow = metrics.viewLeft + metrics.viewWidth - MARGIN -
+              var overflow = edgeLeft + metrics.viewWidth - MARGIN -
                   blockXY.x + (Blockly.RTL ? blockHW.width : 0);
               if (overflow < 0) {
                 block.moveBy(overflow, 0);