Merge pull request #3399 from Snuffleupagus/change-page-shift+space

Enable changing page using Shift+Spacebar in presentation mode

web/viewer.js

@@ -3117,6 +3117,15 @@ window.addEventListener('keydown', function keydown(evt) {
 
   if (cmd === 4) { // shift-key
     switch (evt.keyCode) {
+      case 32: // spacebar
+        if (!PDFView.isPresentationMode &&
+            PDFView.currentScaleValue !== 'page-fit') {
+          break;
+        }
+        PDFView.page--;
+        handled = true;
+        break;
+
       case 82: // 'r'
         PDFView.rotatePages(-90);
         break;