Pagecontainer: Pass triggerData with load event

Fixes gh-7580
Closes gh-7581

Author: Rob DiCiuccio

js/widgets/pagecontainer.js

@@ -550,7 +550,7 @@ define( [
 				// Note that it is the responsibility of the listener/handler
 				// that called preventDefault(), to resolve/reject the
 				// deferred object within the triggerData.
-				if ( this._triggerWithDeprecated( "load" ).event.isDefaultPrevented() ) {
+				if ( this._triggerWithDeprecated( "load", triggerData ).event.isDefaultPrevented() ) {
 					return;
 				}
 

tests/integration/pagecontainer/page_event_sequence_core.js

@@ -98,11 +98,11 @@ asyncTest( "Event sequence during navigation to another page", function() {
 
 			// Deprecated as of 1.4.0
 			{ type: "pageload", target: "the-body",
-				data: { prevPage: undefined, nextPage: undefined, toPage: undefined } },
+				data: { prevPage: "start-page", nextPage: undefined, toPage: "other-page" } },
 
 			// Valid
 			{ type: "pagecontainerload", target: "the-body",
-				data: { prevPage: undefined, nextPage: undefined, toPage: undefined } },
+				data: { prevPage: "start-page", nextPage: undefined, toPage: "other-page" } },
 
 			// Valid - page widget events
 			{ type: "pagebeforecreate", target: "other-page",