Indicate user gesture for mouse down/up while pointer locked.

LayoutTests/pointer-lock/pointerlock-then-fullscreen.html

Index: LayoutTests/pointer-lock/pointerlock-then-fullscreen.html
diff --git a/LayoutTests/pointer-lock/pointerlockchange-event-on-lock-lost.html b/LayoutTests/pointer-lock/pointerlock-then-fullscreen.html
similarity index 63%
copy from LayoutTests/pointer-lock/pointerlockchange-event-on-lock-lost.html
copy to LayoutTests/pointer-lock/pointerlock-then-fullscreen.html
index 2f4ff241f5c9b23b3c03ef070f2f0cd5c8bc4f4a..bbefa35d5f4bacc729d30fcc6effd5ad68a61994 100644
--- a/LayoutTests/pointer-lock/pointerlockchange-event-on-lock-lost.html
+++ b/LayoutTests/pointer-lock/pointerlock-then-fullscreen.html
@@ -9,7 +9,7 @@
   <div id="target1"></div>
 </div>
 <script>
-    description("Test that pointerlockchange event is dispatched when lock is lost.")
+    description("Test pointerlock then fullscreen.")
     window.jsTestIsAsync = true;
     shouldBeDefined("window.testRunner");
 
@@ -23,12 +23,17 @@
         },
         function () {
             shouldBe("document.pointerLockElement", "targetDiv1");
-            expectOnlyChangeEvent("Host initiated unlock.");
-            testRunner.didLosePointerLock();
-            // doNextStep called by event handler.
+            document.body.onmousedown = function () {
+                targetDiv1.webkitRequestFullscreen();
+            }
+            document.onwebkitfullscreenchange = function () {
+                doNextStep();
+            }
+            eventSender.mouseDown();
         },
         function () {
-            shouldBe("document.pointerLockElement", "null");
+            shouldBe("document.pointerLockElement", "targetDiv1");
+            shouldBe("document.webkitFullscreenElement", "targetDiv1");
             doNextStep();
         },
     ];