Add css for table scrolling. Fixes #2027 (#2028)

Author: brollb

src/visualizers/widgets/ExecutionIndex/styles/ExecutionIndexWidget.css

@@ -1,21 +1,14 @@
 /**
- * This file is for any css that you may want for this visualizer.
- *
- * Ideally, you would use the scss file also provided in this directory 
- * and then generate this file automatically from that. However, you can 
- * simply write css if you prefer
+ * This file is for any scss that you may want for this visualizer.
  */
-
 .execution-index.panel-body {
-    padding: 0;
-}
+  padding: 0; }
 
 .execution-index .left {
   position: absolute;
   background-color: #eee;
-}
+  overflow-y: scroll; }
 
 .execution-index .right {
   position: absolute;
-  background-color: #eee;
-}
+  background-color: #eee; }

src/visualizers/widgets/ExecutionIndex/styles/ExecutionIndexWidget.scss

@@ -2,6 +2,17 @@
  * This file is for any scss that you may want for this visualizer.
  */
 
-.execution-index {
-  outline: none;
+.execution-index.panel-body {
+    padding: 0;
+}
+
+.execution-index .left {
+  position: absolute;
+  background-color: #eee;
+  overflow-y: scroll;
+}
+
+.execution-index .right {
+  position: absolute;
+  background-color: #eee;
 }