Overlay scrollbar in webkit browsers

-To prevent scrollbar from offsetting the cells
 those browsers that support overlay scrollbars
 should use it.

Issue: DEB-182

src/main.less

@@ -1,5 +1,6 @@
 /* eslint-disable */
 .qv-object-qlik-smart-pivot {
+  @TableBorder: 1px solid #d3d3d3;
   @KpiTableWidth: 230px;
 
   *,
@@ -32,13 +33,18 @@
   }
 
   table {
-    border-collapse: separate;
-    border-spacing: 1px;
+    border-collapse: collapse;
+    border-spacing: 0;
     width: auto;
+    border-left: @TableBorder;
+    border-right: @TableBorder;
+    border-top: @TableBorder;
   }
 
   td,
   th {
+    border: 1px solid #fff;
+    border-collapse: collapse;
     padding: 5px !important; // prevent overwriting from single object
     white-space: nowrap;
     overflow: hidden;
@@ -64,6 +70,7 @@
   th.main-kpi {
     text-align: center;
     vertical-align: middle;
+    border-bottom: @TableBorder;
   }
 
   .numeric {
@@ -251,10 +258,17 @@
     .row-wrapper {
       height: calc(~"100% - 97px");
       width: 100%;
-      overflow: scroll;
+      overflow: auto;
       padding: 0;
       margin-top: 0;
     }
+
+    // Use overlay-scrollbars for webkit-browsers
+    @media screen and (-webkit-min-device-pixel-ratio: 0) {
+      .row-wrapper {
+        overflow: overlay;
+      }
+    }
   }
 
   // hide scrollbars