Add hook for clicking on trashcan.

core/trashcan.js

@@ -179,6 +179,7 @@ Blockly.Trashcan.prototype.createDom = function() {
   this.svgLid_.setAttributeNS('http://www.w3.org/1999/xlink', 'xlink:href',
       this.workspace_.options.pathToMedia + Blockly.SPRITE.url);
 
+  Blockly.bindEvent_(this.svgGroup_, 'mouseup', this, this.click);
   this.animateLid_();
   return this.svgGroup_;
 };
@@ -282,3 +283,15 @@ Blockly.Trashcan.prototype.animateLid_ = function() {
 Blockly.Trashcan.prototype.close = function() {
   this.setOpen_(false);
 };
+
+/**
+ * Inspect the contents of the trash.
+ */
+Blockly.Trashcan.prototype.click = function() {
+  var dx = this.workspace_.startScrollX - this.workspace_.scrollX;
+  var dy = this.workspace_.startScrollY - this.workspace_.scrollY;
+  if (Math.sqrt(dx * dx + dy * dy) > Blockly.DRAG_RADIUS) {
+    return;
+  }
+  console.log('TODO: Inspect trash.');
+};

core/workspace_svg.js

@@ -99,6 +99,18 @@ Blockly.WorkspaceSvg.prototype.scrollX = 0;
  */
 Blockly.WorkspaceSvg.prototype.scrollY = 0;
 
+/**
+ * Horizontal scroll value when scrolling started.
+ * @type {number}
+ */
+Blockly.WorkspaceSvg.prototype.startScrollX = 0;
+
+/**
+ * Vertical scroll value when scrolling started.
+ * @type {number}
+ */
+Blockly.WorkspaceSvg.prototype.startScrollY = 0;
+
 /**
  * Horizontal distance from mouse to object being dragged.
  * @type {number}