fix(virtual-repeat): auto shrink restored wrong original size.

* This broke the autocompletes height determination, when the matches array is empty.

Fixes #7955.

Closes #8095

src/components/virtualRepeat/virtual-repeater.js

@@ -183,7 +183,7 @@ VirtualRepeatContainerController.prototype.getSize = function() {
 /**
  * Resizes the container.
  * @private
- * @param {number} The new size to set.
+ * @param {number} size The new size to set.
  */
 VirtualRepeatContainerController.prototype.setSize_ = function(size) {
   var dimension = this.getDimensionName_();
@@ -201,6 +201,7 @@ VirtualRepeatContainerController.prototype.unsetSize_ = function() {
 
 /** Instructs the container to re-measure its size. */
 VirtualRepeatContainerController.prototype.updateSize = function() {
+  // If the original size is already determined, we can skip the update.
   if (this.originalSize) return;
 
   this.size = this.isHorizontal()
@@ -274,22 +275,35 @@ VirtualRepeatContainerController.prototype.sizeScroller_ = function(size) {
  */
 VirtualRepeatContainerController.prototype.autoShrink_ = function(size) {
   var shrinkSize = Math.max(size, this.autoShrinkMin * this.repeater.getItemSize());
+
   if (this.autoShrink && shrinkSize !== this.size) {
     if (this.oldElementSize === null) {
       this.oldElementSize = this.$element[0].style[this.getDimensionName_()];
     }
 
     var currentSize = this.originalSize || this.size;
+
     if (!currentSize || shrinkSize < currentSize) {
       if (!this.originalSize) {
         this.originalSize = this.size;
       }
 
+      // Now we update the containers size, because shrinking is enabled.
       this.setSize_(shrinkSize);
     } else if (this.originalSize !== null) {
+      // Set the size back to our initial size.
       this.unsetSize_();
+
+      var _originalSize = this.originalSize;
       this.originalSize = null;
-      this.updateSize();
+
+      // We determine the repeaters size again, if the original size was zero.
+      // The originalSize needs to be null, to be able to determine the size.
+      if (!_originalSize) this.updateSize();
+
+      // Apply the original size or the determined size back to the container, because
+      // it has been overwritten before, in the shrink block.
+      this.setSize_(_originalSize || this.size);
     }
 
     this.repeater.containerUpdated();