Fixes maxOverlayHieght #630

src/vaadin-combo-box-dropdown-wrapper.html

@@ -254,12 +254,10 @@
       _maxOverlayHeight(targetRect) {
         const margin = 8;
         const minHeight = 116; // Height of two items in combo-box
-        const bottom = Math.min(window.innerHeight, document.body.scrollHeight - document.body.scrollTop);
-
         if (this.$.dropdown.alignedAbove) {
           return Math.max(targetRect.top - margin + Math.min(document.body.scrollTop, 0), minHeight) + 'px';
         } else {
-          return Math.max(bottom - targetRect.bottom - margin, minHeight) + 'px';
+          return Math.max(document.documentElement.clientHeight - targetRect.bottom - margin, minHeight) + 'px';
         }
       }
 

test/scrolling.html

@@ -45,6 +45,26 @@
         });
       });
 
+      describe('the height of scroller', () => {
+        beforeEach(() => {
+          const items = [];
+
+          for (let i = 0; i < 100; i++) {
+            items.push(i.toString());
+          }
+
+          combobox.items = items;
+        });
+
+        it('should the height of scroller extends taller than mins-height for many items', () => {
+          combobox.open();
+
+          const scroller = combobox.$.overlay._scroller;
+          const height = parseFloat(getComputedStyle(scroller).height.split('p')[0]);
+          expect(height).to.above(116);
+        });
+      });
+
       describe('scrolling position', () => {
         beforeEach(() => {
           const items = [];