[Core] Bring in core bundle from sandbox

Bring in bundle platform/core from the sandbox
branch, in preparation for clean up, tests, and
integration. WTD-573

platform/core/src/actions/ActionProvider.js

@@ -0,0 +1,88 @@
+/*global define,Promise*/
+
+/**
+ * Module defining ActionProvider. Created by vwoeltje on 11/7/14.
+ */
+define(
+    [],
+    function () {
+        "use strict";
+
+        /**
+         *
+         * @constructor
+         */
+        function ActionProvider(actions) {
+            var actionsByKey = {},
+                actionsByCategory = {};
+
+            function instantiateAction(Action, context) {
+                var action = new Action(context),
+                    metadata;
+
+                // Provide a getMetadata method that echos
+                // declarative bindings, as well as context,
+                // unless the action has defined its own.
+                if (!action.getMetadata) {
+                    metadata = Object.create(Action.definition);
+                    metadata.context = context;
+                    action.getMetadata = function () {
+                        return metadata;
+                    };
+                }
+
+                return action;
+            }
+
+            function createIfApplicable(actions, context) {
+                return (actions || []).filter(function (Action) {
+                    return Action.appliesTo ?
+                            Action.appliesTo(context) : true;
+                }).map(function (Action) {
+                    return instantiateAction(Action, context);
+                });
+            }
+
+            function getActions(actionContext) {
+                var context = (actionContext || {}),
+                    category = context.category,
+                    key = context.key,
+                    candidates;
+
+                candidates = actions;
+                if (key) {
+                    candidates = actionsByKey[key];
+                    if (category) {
+                        candidates = candidates.filter(function (Action) {
+                            return Action.category === category;
+                        });
+                    }
+                } else if (category) {
+                    candidates = actionsByCategory[category];
+                }
+
+                return createIfApplicable(candidates, context);
+            }
+
+            // Build up look-up tables
+            actions.forEach(function (Action) {
+                if (Action.category) {
+                    actionsByCategory[Action.category] =
+                        actionsByCategory[Action.category] || [];
+                    actionsByCategory[Action.category].push(Action);
+                }
+                if (Action.key) {
+                    actionsByKey[Action.key] =
+                        actionsByKey[Action.key] || [];
+                    actionsByKey[Action.key].push(Action);
+                }
+            });
+
+            return {
+                getActions: getActions
+            };
+        }
+
+        return ActionProvider;
+    }
+);